diff --git a/sys/fs/msdosfs/msdosfs_fat.c b/sys/fs/msdosfs/msdosfs_fat.c index e6d9b671e7d7..2d50d30f33b3 100644 --- a/sys/fs/msdosfs/msdosfs_fat.c +++ b/sys/fs/msdosfs/msdosfs_fat.c @@ -1,1210 +1,1216 @@ /* $FreeBSD$ */ /* $NetBSD: msdosfs_fat.c,v 1.28 1997/11/17 15:36:49 ws Exp $ */ /*- * SPDX-License-Identifier: BSD-4-Clause * * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. * Copyright (C) 1994, 1995, 1997 TooLs GmbH. * All rights reserved. * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by TooLs GmbH. * 4. The name of TooLs GmbH may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /*- * Written by Paul Popelka (paulp@uts.amdahl.com) * * You can do anything you want with this software, just don't say you wrote * it, and don't remove this notice. * * This software is provided "as is". * * The author supplies this software to be publicly redistributed on the * understanding that the author is not responsible for the correct * functioning of this software in any circumstances and is not liable for * any damages caused by this software. * * October 1992 */ #include #include #include #include #include #include #include #include #include #include #include #define FULL_RUN ((u_int)0xffffffff) static int chainalloc(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got); static int chainlength(struct msdosfsmount *pmp, u_long start, u_long count); static void fatblock(struct msdosfsmount *pmp, u_long ofs, u_long *bnp, u_long *sizep, u_long *bop); static int fatchain(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith); static void fc_lookup(struct denode *dep, u_long findcn, u_long *frcnp, u_long *fsrcnp); static void updatefats(struct msdosfsmount *pmp, struct buf *bp, u_long fatbn); static __inline void usemap_alloc(struct msdosfsmount *pmp, u_long cn); static int usemap_free(struct msdosfsmount *pmp, u_long cn); static int clusteralloc1(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got); static void fatblock(struct msdosfsmount *pmp, u_long ofs, u_long *bnp, u_long *sizep, u_long *bop) { - u_long bn, size; + u_long bn, size, fatblocksec; + fatblocksec = pmp->pm_fatblocksec; + if (FAT12(pmp) && fatblocksec % 3 != 0) { + fatblocksec *= 3; + if (fatblocksec % 6 == 0) + fatblocksec /= 2; + } bn = ofs / pmp->pm_fatblocksize * pmp->pm_fatblocksec; - size = min(pmp->pm_fatblocksec, pmp->pm_FATsecs - bn) - * DEV_BSIZE; + size = roundup(min(fatblocksec, pmp->pm_FATsecs - bn) * DEV_BSIZE, + pmp->pm_BlkPerSec * DEV_BSIZE); bn += pmp->pm_fatblk + pmp->pm_curfat * pmp->pm_FATsecs; if (bnp) *bnp = bn; if (sizep) *sizep = size; if (bop) *bop = ofs % pmp->pm_fatblocksize; } /* * Map the logical cluster number of a file into a physical disk sector * that is filesystem relative. * * dep - address of denode representing the file of interest * findcn - file relative cluster whose filesystem relative cluster number * and/or block number are/is to be found * bnp - address of where to place the filesystem relative block number. * If this pointer is null then don't return this quantity. * cnp - address of where to place the filesystem relative cluster number. * If this pointer is null then don't return this quantity. * sp - pointer to returned block size * * NOTE: Either bnp or cnp must be non-null. * This function has one side effect. If the requested file relative cluster * is beyond the end of file, then the actual number of clusters in the file * is returned in *cnp. This is useful for determining how long a directory is. * If cnp is null, nothing is returned. */ int pcbmap(struct denode *dep, u_long findcn, daddr_t *bnp, u_long *cnp, int *sp) { int error; u_long i; u_long cn; u_long prevcn = 0; /* XXX: prevcn could be used unititialized */ u_long byteoffset; u_long bn; u_long bo; struct buf *bp = NULL; u_long bp_bn = -1; struct msdosfsmount *pmp = dep->de_pmp; u_long bsize; KASSERT(bnp != NULL || cnp != NULL || sp != NULL, ("pcbmap: extra call")); ASSERT_VOP_ELOCKED(DETOV(dep), "pcbmap"); cn = dep->de_StartCluster; /* * The "file" that makes up the root directory is contiguous, * permanently allocated, of fixed size, and is not made up of * clusters. If the cluster number is beyond the end of the root * directory, then return the number of clusters in the file. */ if (cn == MSDOSFSROOT) { if (dep->de_Attributes & ATTR_DIRECTORY) { if (de_cn2off(pmp, findcn) >= dep->de_FileSize) { if (cnp) *cnp = de_bn2cn(pmp, pmp->pm_rootdirsize); return (E2BIG); } if (bnp) *bnp = pmp->pm_rootdirblk + de_cn2bn(pmp, findcn); if (cnp) *cnp = MSDOSFSROOT; if (sp) *sp = min(pmp->pm_bpcluster, dep->de_FileSize - de_cn2off(pmp, findcn)); return (0); } else { /* just an empty file */ if (cnp) *cnp = 0; return (E2BIG); } } /* * All other files do I/O in cluster sized blocks */ if (sp) *sp = pmp->pm_bpcluster; /* * Rummage around in the FAT cache, maybe we can avoid tromping * through every FAT entry for the file. And, keep track of how far * off the cache was from where we wanted to be. */ i = 0; fc_lookup(dep, findcn, &i, &cn); /* * Handle all other files or directories the normal way. */ for (; i < findcn; i++) { /* * Stop with all reserved clusters, not just with EOF. */ if ((cn | ~pmp->pm_fatmask) >= CLUST_RSRVD) goto hiteof; byteoffset = FATOFS(pmp, cn); fatblock(pmp, byteoffset, &bn, &bsize, &bo); if (bn != bp_bn) { if (bp) brelse(bp); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error) { return (error); } bp_bn = bn; } prevcn = cn; if (bo >= bsize) { if (bp) brelse(bp); return (EIO); } if (FAT32(pmp)) cn = getulong(bp->b_data + bo); else cn = getushort(bp->b_data + bo); if (FAT12(pmp) && (prevcn & 1)) cn >>= 4; cn &= pmp->pm_fatmask; /* * Force the special cluster numbers * to be the same for all cluster sizes * to let the rest of msdosfs handle * all cases the same. */ if ((cn | ~pmp->pm_fatmask) >= CLUST_RSRVD) cn |= ~pmp->pm_fatmask; } if (!MSDOSFSEOF(pmp, cn)) { if (bp) brelse(bp); if (bnp) *bnp = cntobn(pmp, cn); if (cnp) *cnp = cn; fc_setcache(dep, FC_LASTMAP, i, cn); return (0); } hiteof:; if (cnp) *cnp = i; if (bp) brelse(bp); /* update last file cluster entry in the FAT cache */ fc_setcache(dep, FC_LASTFC, i - 1, prevcn); return (E2BIG); } /* * Find the closest entry in the FAT cache to the cluster we are looking * for. */ static void fc_lookup(struct denode *dep, u_long findcn, u_long *frcnp, u_long *fsrcnp) { int i; u_long cn; struct fatcache *closest = NULL; ASSERT_VOP_LOCKED(DETOV(dep), "fc_lookup"); for (i = 0; i < FC_SIZE; i++) { cn = dep->de_fc[i].fc_frcn; if (cn != FCE_EMPTY && cn <= findcn) { if (closest == NULL || cn > closest->fc_frcn) closest = &dep->de_fc[i]; } } if (closest) { *frcnp = closest->fc_frcn; *fsrcnp = closest->fc_fsrcn; } } /* * Purge the FAT cache in denode dep of all entries relating to file * relative cluster frcn and beyond. */ void fc_purge(struct denode *dep, u_int frcn) { int i; struct fatcache *fcp; ASSERT_VOP_ELOCKED(DETOV(dep), "fc_purge"); fcp = dep->de_fc; for (i = 0; i < FC_SIZE; i++, fcp++) { if (fcp->fc_frcn >= frcn) fcp->fc_frcn = FCE_EMPTY; } } /* * Update the FAT. * If mirroring the FAT, update all copies, with the first copy as last. * Else update only the current FAT (ignoring the others). * * pmp - msdosfsmount structure for filesystem to update * bp - addr of modified FAT block * fatbn - block number relative to begin of filesystem of the modified FAT block. */ static void updatefats(struct msdosfsmount *pmp, struct buf *bp, u_long fatbn) { struct buf *bpn; int cleanfat, i; #ifdef MSDOSFS_DEBUG printf("updatefats(pmp %p, bp %p, fatbn %lu)\n", pmp, bp, fatbn); #endif if (pmp->pm_flags & MSDOSFS_FATMIRROR) { /* * Now copy the block(s) of the modified FAT to the other copies of * the FAT and write them out. This is faster than reading in the * other FATs and then writing them back out. This could tie up * the FAT for quite a while. Preventing others from accessing it. * To prevent us from going after the FAT quite so much we use * delayed writes, unless they specified "synchronous" when the * filesystem was mounted. If synch is asked for then use * bwrite()'s and really slow things down. */ if (fatbn != pmp->pm_fatblk || FAT12(pmp)) cleanfat = 0; else if (FAT16(pmp)) cleanfat = 16; else cleanfat = 32; for (i = 1; i < pmp->pm_FATs; i++) { fatbn += pmp->pm_FATsecs; /* getblk() never fails */ bpn = getblk(pmp->pm_devvp, fatbn, bp->b_bcount, 0, 0, 0); memcpy(bpn->b_data, bp->b_data, bp->b_bcount); /* Force the clean bit on in the other copies. */ if (cleanfat == 16) ((uint8_t *)bpn->b_data)[3] |= 0x80; else if (cleanfat == 32) ((uint8_t *)bpn->b_data)[7] |= 0x08; if (pmp->pm_mountp->mnt_flag & MNT_SYNCHRONOUS) bwrite(bpn); else bdwrite(bpn); } } /* * Write out the first (or current) FAT last. */ if (pmp->pm_mountp->mnt_flag & MNT_SYNCHRONOUS) bwrite(bp); else bdwrite(bp); } /* * Updating entries in 12 bit FATs is a pain in the butt. * * The following picture shows where nibbles go when moving from a 12 bit * cluster number into the appropriate bytes in the FAT. * * byte m byte m+1 byte m+2 * +----+----+ +----+----+ +----+----+ * | 0 1 | | 2 3 | | 4 5 | FAT bytes * +----+----+ +----+----+ +----+----+ * * +----+----+----+ +----+----+----+ * | 3 0 1 | | 4 5 2 | * +----+----+----+ +----+----+----+ * cluster n cluster n+1 * * Where n is even. m = n + (n >> 2) * */ static __inline void usemap_alloc(struct msdosfsmount *pmp, u_long cn) { MSDOSFS_ASSERT_MP_LOCKED(pmp); KASSERT(cn <= pmp->pm_maxcluster, ("cn too large %lu %lu", cn, pmp->pm_maxcluster)); KASSERT((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0, ("usemap_alloc on ro msdosfs mount")); KASSERT((pmp->pm_inusemap[cn / N_INUSEBITS] & (1U << (cn % N_INUSEBITS))) == 0, ("Allocating used sector %ld %ld %x", cn, cn % N_INUSEBITS, (unsigned)pmp->pm_inusemap[cn / N_INUSEBITS])); pmp->pm_inusemap[cn / N_INUSEBITS] |= 1U << (cn % N_INUSEBITS); KASSERT(pmp->pm_freeclustercount > 0, ("usemap_alloc: too little")); pmp->pm_freeclustercount--; pmp->pm_flags |= MSDOSFS_FSIMOD; } static int usemap_free(struct msdosfsmount *pmp, u_long cn) { MSDOSFS_ASSERT_MP_LOCKED(pmp); KASSERT(cn <= pmp->pm_maxcluster, ("cn too large %lu %lu", cn, pmp->pm_maxcluster)); KASSERT((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0, ("usemap_free on ro msdosfs mount")); if ((pmp->pm_inusemap[cn / N_INUSEBITS] & (1U << (cn % N_INUSEBITS))) == 0) { printf("%s: Freeing unused sector %ld %ld %x\n", pmp->pm_mountp->mnt_stat.f_mntonname, cn, cn % N_INUSEBITS, (unsigned)pmp->pm_inusemap[cn / N_INUSEBITS]); msdosfs_integrity_error(pmp); return (EINTEGRITY); } pmp->pm_freeclustercount++; pmp->pm_flags |= MSDOSFS_FSIMOD; pmp->pm_inusemap[cn / N_INUSEBITS] &= ~(1U << (cn % N_INUSEBITS)); return (0); } void clusterfree(struct msdosfsmount *pmp, u_long cluster) { int error; u_long oldcn; error = fatentry(FAT_GET_AND_SET, pmp, cluster, &oldcn, MSDOSFSFREE); if (error != 0) return; /* * If the cluster was successfully marked free, then update * the count of free clusters, and turn off the "allocated" * bit in the "in use" cluster bit map. */ MSDOSFS_LOCK_MP(pmp); error = usemap_free(pmp, cluster); MSDOSFS_UNLOCK_MP(pmp); } /* * Get or Set or 'Get and Set' the cluster'th entry in the FAT. * * function - whether to get or set a FAT entry * pmp - address of the msdosfsmount structure for the filesystem * whose FAT is to be manipulated. * cn - which cluster is of interest * oldcontents - address of a word that is to receive the contents of the * cluster'th entry if this is a get function * newcontents - the new value to be written into the cluster'th element of * the FAT if this is a set function. * * This function can also be used to free a cluster by setting the FAT entry * for a cluster to 0. * * All copies of the FAT are updated if this is a set function. NOTE: If * fatentry() marks a cluster as free it does not update the inusemap in * the msdosfsmount structure. This is left to the caller. */ int fatentry(int function, struct msdosfsmount *pmp, u_long cn, u_long *oldcontents, u_long newcontents) { int error; u_long readcn; u_long bn, bo, bsize, byteoffset; struct buf *bp; #ifdef MSDOSFS_DEBUG printf("fatentry(func %d, pmp %p, clust %lu, oldcon %p, newcon %lx)\n", function, pmp, cn, oldcontents, newcontents); #endif #ifdef DIAGNOSTIC /* * Be sure they asked us to do something. */ if ((function & (FAT_SET | FAT_GET)) == 0) { #ifdef MSDOSFS_DEBUG printf("fatentry(): function code doesn't specify get or set\n"); #endif return (EINVAL); } /* * If they asked us to return a cluster number but didn't tell us * where to put it, give them an error. */ if ((function & FAT_GET) && oldcontents == NULL) { #ifdef MSDOSFS_DEBUG printf("fatentry(): get function with no place to put result\n"); #endif return (EINVAL); } #endif /* * Be sure the requested cluster is in the filesystem. */ if (cn < CLUST_FIRST || cn > pmp->pm_maxcluster) return (EINVAL); byteoffset = FATOFS(pmp, cn); fatblock(pmp, byteoffset, &bn, &bsize, &bo); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error) { return (error); } if (function & FAT_GET) { if (FAT32(pmp)) readcn = getulong(bp->b_data + bo); else readcn = getushort(bp->b_data + bo); if (FAT12(pmp) & (cn & 1)) readcn >>= 4; readcn &= pmp->pm_fatmask; /* map reserved FAT entries to same values for all FATs */ if ((readcn | ~pmp->pm_fatmask) >= CLUST_RSRVD) readcn |= ~pmp->pm_fatmask; *oldcontents = readcn; } if (function & FAT_SET) { switch (pmp->pm_fatmask) { case FAT12_MASK: readcn = getushort(bp->b_data + bo); if (cn & 1) { readcn &= 0x000f; readcn |= newcontents << 4; } else { readcn &= 0xf000; readcn |= newcontents & 0xfff; } putushort(bp->b_data + bo, readcn); break; case FAT16_MASK: putushort(bp->b_data + bo, newcontents); break; case FAT32_MASK: /* * According to spec we have to retain the * high order bits of the FAT entry. */ readcn = getulong(bp->b_data + bo); readcn &= ~FAT32_MASK; readcn |= newcontents & FAT32_MASK; putulong(bp->b_data + bo, readcn); break; } updatefats(pmp, bp, bn); bp = NULL; pmp->pm_fmod = 1; } if (bp) brelse(bp); return (0); } /* * Update a contiguous cluster chain * * pmp - mount point * start - first cluster of chain * count - number of clusters in chain * fillwith - what to write into FAT entry of last cluster */ static int fatchain(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith) { int error; u_long bn, bo, bsize, byteoffset, readcn, newc; struct buf *bp; #ifdef MSDOSFS_DEBUG printf("fatchain(pmp %p, start %lu, count %lu, fillwith %lx)\n", pmp, start, count, fillwith); #endif /* * Be sure the clusters are in the filesystem. */ if (start < CLUST_FIRST || start + count - 1 > pmp->pm_maxcluster) return (EINVAL); while (count > 0) { byteoffset = FATOFS(pmp, start); fatblock(pmp, byteoffset, &bn, &bsize, &bo); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error) { return (error); } while (count > 0) { start++; newc = --count > 0 ? start : fillwith; switch (pmp->pm_fatmask) { case FAT12_MASK: readcn = getushort(bp->b_data + bo); if (start & 1) { readcn &= 0xf000; readcn |= newc & 0xfff; } else { readcn &= 0x000f; readcn |= newc << 4; } putushort(bp->b_data + bo, readcn); bo++; if (!(start & 1)) bo++; break; case FAT16_MASK: putushort(bp->b_data + bo, newc); bo += 2; break; case FAT32_MASK: readcn = getulong(bp->b_data + bo); readcn &= ~pmp->pm_fatmask; readcn |= newc & pmp->pm_fatmask; putulong(bp->b_data + bo, readcn); bo += 4; break; } if (bo >= bsize) break; } updatefats(pmp, bp, bn); } pmp->pm_fmod = 1; return (0); } /* * Check the length of a free cluster chain starting at start. * * pmp - mount point * start - start of chain * count - maximum interesting length */ static int chainlength(struct msdosfsmount *pmp, u_long start, u_long count) { u_long idx, max_idx; u_int map; u_long len; MSDOSFS_ASSERT_MP_LOCKED(pmp); if (start > pmp->pm_maxcluster) return (0); max_idx = pmp->pm_maxcluster / N_INUSEBITS; idx = start / N_INUSEBITS; start %= N_INUSEBITS; map = pmp->pm_inusemap[idx]; map &= ~((1U << start) - 1); if (map) { len = ffs(map) - 1 - start; len = MIN(len, count); if (start + len > pmp->pm_maxcluster) len = pmp->pm_maxcluster - start + 1; return (len); } len = N_INUSEBITS - start; if (len >= count) { len = count; if (start + len > pmp->pm_maxcluster) len = pmp->pm_maxcluster - start + 1; return (len); } while (++idx <= max_idx) { if (len >= count) break; map = pmp->pm_inusemap[idx]; if (map) { len += ffs(map) - 1; break; } len += N_INUSEBITS; } len = MIN(len, count); if (start + len > pmp->pm_maxcluster) len = pmp->pm_maxcluster - start + 1; return (len); } /* * Allocate contigous free clusters. * * pmp - mount point. * start - start of cluster chain. * count - number of clusters to allocate. * fillwith - put this value into the FAT entry for the * last allocated cluster. * retcluster - put the first allocated cluster's number here. * got - how many clusters were actually allocated. */ static int chainalloc(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got) { int error; u_long cl, n; MSDOSFS_ASSERT_MP_LOCKED(pmp); KASSERT((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0, ("chainalloc on ro msdosfs mount")); for (cl = start, n = count; n-- > 0;) usemap_alloc(pmp, cl++); pmp->pm_nxtfree = start + count; if (pmp->pm_nxtfree > pmp->pm_maxcluster) pmp->pm_nxtfree = CLUST_FIRST; pmp->pm_flags |= MSDOSFS_FSIMOD; error = fatchain(pmp, start, count, fillwith); if (error != 0) { for (cl = start, n = count; n-- > 0;) (void)usemap_free(pmp, cl++); return (error); } #ifdef MSDOSFS_DEBUG printf("clusteralloc(): allocated cluster chain at %lu (%lu clusters)\n", start, count); #endif if (retcluster) *retcluster = start; if (got) *got = count; return (0); } /* * Allocate contiguous free clusters. * * pmp - mount point. * start - preferred start of cluster chain. * count - number of clusters requested. * fillwith - put this value into the FAT entry for the * last allocated cluster. * retcluster - put the first allocated cluster's number here. * got - how many clusters were actually allocated. */ int clusteralloc(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got) { int error; MSDOSFS_LOCK_MP(pmp); error = clusteralloc1(pmp, start, count, fillwith, retcluster, got); MSDOSFS_UNLOCK_MP(pmp); return (error); } static int clusteralloc1(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got) { u_long idx; u_long len, newst, foundl, cn, l; u_long foundcn = 0; /* XXX: foundcn could be used unititialized */ u_int map; MSDOSFS_ASSERT_MP_LOCKED(pmp); #ifdef MSDOSFS_DEBUG printf("clusteralloc(): find %lu clusters\n", count); #endif if (start) { if ((len = chainlength(pmp, start, count)) >= count) return (chainalloc(pmp, start, count, fillwith, retcluster, got)); } else len = 0; newst = pmp->pm_nxtfree; foundl = 0; for (cn = newst; cn <= pmp->pm_maxcluster;) { idx = cn / N_INUSEBITS; map = pmp->pm_inusemap[idx]; map |= (1U << (cn % N_INUSEBITS)) - 1; if (map != FULL_RUN) { cn = idx * N_INUSEBITS + ffs(map ^ FULL_RUN) - 1; if ((l = chainlength(pmp, cn, count)) >= count) return (chainalloc(pmp, cn, count, fillwith, retcluster, got)); if (l > foundl) { foundcn = cn; foundl = l; } cn += l + 1; continue; } cn += N_INUSEBITS - cn % N_INUSEBITS; } for (cn = 0; cn < newst;) { idx = cn / N_INUSEBITS; map = pmp->pm_inusemap[idx]; map |= (1U << (cn % N_INUSEBITS)) - 1; if (map != FULL_RUN) { cn = idx * N_INUSEBITS + ffs(map ^ FULL_RUN) - 1; if ((l = chainlength(pmp, cn, count)) >= count) return (chainalloc(pmp, cn, count, fillwith, retcluster, got)); if (l > foundl) { foundcn = cn; foundl = l; } cn += l + 1; continue; } cn += N_INUSEBITS - cn % N_INUSEBITS; } if (!foundl) return (ENOSPC); if (len) return (chainalloc(pmp, start, len, fillwith, retcluster, got)); else return (chainalloc(pmp, foundcn, foundl, fillwith, retcluster, got)); } /* * Free a chain of clusters. * * pmp - address of the msdosfs mount structure for the filesystem * containing the cluster chain to be freed. * startcluster - number of the 1st cluster in the chain of clusters to be * freed. */ int freeclusterchain(struct msdosfsmount *pmp, u_long cluster) { int error; struct buf *bp = NULL; u_long bn, bo, bsize, byteoffset; u_long readcn, lbn = -1; MSDOSFS_LOCK_MP(pmp); while (cluster >= CLUST_FIRST && cluster <= pmp->pm_maxcluster) { byteoffset = FATOFS(pmp, cluster); fatblock(pmp, byteoffset, &bn, &bsize, &bo); if (lbn != bn) { if (bp) updatefats(pmp, bp, lbn); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error) { MSDOSFS_UNLOCK_MP(pmp); return (error); } lbn = bn; } error = usemap_free(pmp, cluster); if (error != 0) { updatefats(pmp, bp, lbn); MSDOSFS_UNLOCK_MP(pmp); return (error); } switch (pmp->pm_fatmask) { case FAT12_MASK: readcn = getushort(bp->b_data + bo); if (cluster & 1) { cluster = readcn >> 4; readcn &= 0x000f; readcn |= MSDOSFSFREE << 4; } else { cluster = readcn; readcn &= 0xf000; readcn |= MSDOSFSFREE & 0xfff; } putushort(bp->b_data + bo, readcn); break; case FAT16_MASK: cluster = getushort(bp->b_data + bo); putushort(bp->b_data + bo, MSDOSFSFREE); break; case FAT32_MASK: cluster = getulong(bp->b_data + bo); putulong(bp->b_data + bo, (MSDOSFSFREE & FAT32_MASK) | (cluster & ~FAT32_MASK)); break; } cluster &= pmp->pm_fatmask; if ((cluster | ~pmp->pm_fatmask) >= CLUST_RSRVD) cluster |= pmp->pm_fatmask; } if (bp) updatefats(pmp, bp, bn); MSDOSFS_UNLOCK_MP(pmp); return (0); } /* * Read in FAT blocks looking for free clusters. For every free cluster * found turn off its corresponding bit in the pm_inusemap. */ int fillinusemap(struct msdosfsmount *pmp) { struct buf *bp; u_long bn, bo, bsize, byteoffset, cn, readcn; int error; MSDOSFS_ASSERT_MP_LOCKED(pmp); bp = NULL; /* * Mark all clusters in use, we mark the free ones in the FAT scan * loop further down. */ for (cn = 0; cn < (pmp->pm_maxcluster + N_INUSEBITS) / N_INUSEBITS; cn++) pmp->pm_inusemap[cn] = FULL_RUN; /* * Figure how many free clusters are in the filesystem by ripping * through the FAT counting the number of entries whose content is * zero. These represent free clusters. */ pmp->pm_freeclustercount = 0; for (cn = 0; cn <= pmp->pm_maxcluster; cn++) { byteoffset = FATOFS(pmp, cn); bo = byteoffset % pmp->pm_fatblocksize; if (bo == 0) { /* Read new FAT block */ if (bp != NULL) brelse(bp); fatblock(pmp, byteoffset, &bn, &bsize, NULL); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error != 0) return (error); } if (FAT32(pmp)) readcn = getulong(bp->b_data + bo); else readcn = getushort(bp->b_data + bo); if (FAT12(pmp) && (cn & 1)) readcn >>= 4; readcn &= pmp->pm_fatmask; /* * Check if the FAT ID matches the BPB's media descriptor and * all other bits are set to 1. */ if (cn == 0 && readcn != ((pmp->pm_fatmask & 0xffffff00) | pmp->pm_bpb.bpbMedia)) { #ifdef MSDOSFS_DEBUG printf("mountmsdosfs(): Media descriptor in BPB" "does not match FAT ID\n"); #endif brelse(bp); return (EINVAL); } else if (readcn == CLUST_FREE) { error = usemap_free(pmp, cn); if (error != 0) { brelse(bp); return (error); } } } if (bp != NULL) brelse(bp); for (cn = pmp->pm_maxcluster + 1; cn < (pmp->pm_maxcluster + N_INUSEBITS) / N_INUSEBITS; cn++) pmp->pm_inusemap[cn / N_INUSEBITS] |= 1U << (cn % N_INUSEBITS); return (0); } /* * Allocate a new cluster and chain it onto the end of the file. * * dep - the file to extend * count - number of clusters to allocate * bpp - where to return the address of the buf header for the first new * file block * ncp - where to put cluster number of the first newly allocated cluster * If this pointer is 0, do not return the cluster number. * flags - see fat.h * * NOTE: This function is not responsible for turning on the DE_UPDATE bit of * the de_flag field of the denode and it does not change the de_FileSize * field. This is left for the caller to do. */ int extendfile(struct denode *dep, u_long count, struct buf **bpp, u_long *ncp, int flags) { int error; u_long frcn; u_long cn, got; struct msdosfsmount *pmp = dep->de_pmp; struct buf *bp; daddr_t blkno; /* * Don't try to extend the root directory */ if (dep->de_StartCluster == MSDOSFSROOT && (dep->de_Attributes & ATTR_DIRECTORY)) { #ifdef MSDOSFS_DEBUG printf("extendfile(): attempt to extend root directory\n"); #endif return (ENOSPC); } /* * If the "file's last cluster" cache entry is empty, and the file * is not empty, then fill the cache entry by calling pcbmap(). */ if (dep->de_fc[FC_LASTFC].fc_frcn == FCE_EMPTY && dep->de_StartCluster != 0) { error = pcbmap(dep, 0xffff, 0, &cn, 0); /* we expect it to return E2BIG */ if (error != E2BIG) return (error); } dep->de_fc[FC_NEXTTOLASTFC].fc_frcn = dep->de_fc[FC_LASTFC].fc_frcn; dep->de_fc[FC_NEXTTOLASTFC].fc_fsrcn = dep->de_fc[FC_LASTFC].fc_fsrcn; while (count > 0) { /* * Allocate a new cluster chain and cat onto the end of the * file. If the file is empty we make de_StartCluster point * to the new block. Note that de_StartCluster being 0 is * sufficient to be sure the file is empty since we exclude * attempts to extend the root directory above, and the root * dir is the only file with a startcluster of 0 that has * blocks allocated (sort of). */ if (dep->de_StartCluster == 0) cn = 0; else cn = dep->de_fc[FC_LASTFC].fc_fsrcn + 1; error = clusteralloc(pmp, cn, count, CLUST_EOFE, &cn, &got); if (error) return (error); count -= got; /* * Give them the filesystem relative cluster number if they want * it. */ if (ncp) { *ncp = cn; ncp = NULL; } if (dep->de_StartCluster == 0) { dep->de_StartCluster = cn; frcn = 0; } else { error = fatentry(FAT_SET, pmp, dep->de_fc[FC_LASTFC].fc_fsrcn, 0, cn); if (error) { clusterfree(pmp, cn); return (error); } frcn = dep->de_fc[FC_LASTFC].fc_frcn + 1; } /* * Update the "last cluster of the file" entry in the * denode's FAT cache. */ fc_setcache(dep, FC_LASTFC, frcn + got - 1, cn + got - 1); if (flags & DE_CLEAR) { while (got-- > 0) { /* * Get the buf header for the new block of the file. */ if (dep->de_Attributes & ATTR_DIRECTORY) bp = getblk(pmp->pm_devvp, cntobn(pmp, cn++), pmp->pm_bpcluster, 0, 0, 0); else { bp = getblk(DETOV(dep), frcn++, pmp->pm_bpcluster, 0, 0, 0); /* * Do the bmap now, as in msdosfs_write */ if (pcbmap(dep, bp->b_lblkno, &blkno, 0, 0)) bp->b_blkno = -1; if (bp->b_blkno == -1) panic("extendfile: pcbmap"); else bp->b_blkno = blkno; } clrbuf(bp); if (bpp) { *bpp = bp; bpp = NULL; } else { bdwrite(bp); } if (vm_page_count_severe() || buf_dirty_count_severe()) vn_fsync_buf(DETOV(dep), MNT_WAIT); } } } return (0); } /*- * Routine to mark a FAT16 or FAT32 volume as "clean" or "dirty" by * manipulating the upper bit of the FAT entry for cluster 1. Note that * this bit is not defined for FAT12 volumes, which are always assumed to * be clean. * * The fatentry() routine only works on cluster numbers that a file could * occupy, so it won't manipulate the entry for cluster 1. So we have to do * it here. The code was stolen from fatentry() and tailored for cluster 1. * * Inputs: * pmp The MS-DOS volume to mark * dirty Non-zero if the volume should be marked dirty; zero if it * should be marked clean * * Result: * 0 Success * EROFS Volume is read-only * ? (other errors from called routines) */ int markvoldirty_upgrade(struct msdosfsmount *pmp, bool dirty, bool rw_upgrade) { struct buf *bp; u_long bn, bo, bsize, byteoffset, fatval; int error; /* * FAT12 does not support a "clean" bit, so don't do anything for * FAT12. */ if (FAT12(pmp)) return (0); /* * Can't change the bit on a read-only filesystem, except as part of * ro->rw upgrade. */ if ((pmp->pm_flags & MSDOSFSMNT_RONLY) != 0 && !rw_upgrade) return (EROFS); /* * Fetch the block containing the FAT entry. It is given by the * pseudo-cluster 1. */ byteoffset = FATOFS(pmp, 1); fatblock(pmp, byteoffset, &bn, &bsize, &bo); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error) return (error); /* * Get the current value of the FAT entry and set/clear the relevant * bit. Dirty means clear the "clean" bit; clean means set the * "clean" bit. */ if (FAT32(pmp)) { /* FAT32 uses bit 27. */ fatval = getulong(&bp->b_data[bo]); if (dirty) fatval &= 0xF7FFFFFF; else fatval |= 0x08000000; putulong(&bp->b_data[bo], fatval); } else { /* Must be FAT16; use bit 15. */ fatval = getushort(&bp->b_data[bo]); if (dirty) fatval &= 0x7FFF; else fatval |= 0x8000; putushort(&bp->b_data[bo], fatval); } /* * The concern here is that a devvp may be readonly, without reporting * itself as such through the usual channels. In that case, we'd like * it if attempting to mount msdosfs rw didn't panic the system. * * markvoldirty is invoked as the first write on backing devvps when * either msdosfs is mounted for the first time, or a ro mount is * upgraded to rw. * * In either event, if a write error occurs dirtying the volume: * - No user data has been permitted to be written to cache yet. * - We can abort the high-level operation (mount, or ro->rw) safely. * - We don't derive any benefit from leaving a zombie dirty buf in * the cache that can not be cleaned or evicted. * * So, mark B_INVALONERR to have bwrite() -> brelse() detect that * condition and force-invalidate our write to the block if it occurs. * * PR 210316 provides more context on the discovery and diagnosis of * the problem, as well as earlier attempts to solve it. */ bp->b_flags |= B_INVALONERR; /* Write out the modified FAT block synchronously. */ return (bwrite(bp)); } diff --git a/sys/fs/msdosfs/msdosfs_vfsops.c b/sys/fs/msdosfs/msdosfs_vfsops.c index e2b1fd6b91f5..87e150e0e18a 100644 --- a/sys/fs/msdosfs/msdosfs_vfsops.c +++ b/sys/fs/msdosfs/msdosfs_vfsops.c @@ -1,1196 +1,1199 @@ /* $FreeBSD$ */ /* $NetBSD: msdosfs_vfsops.c,v 1.51 1997/11/17 15:36:58 ws Exp $ */ /*- * SPDX-License-Identifier: BSD-4-Clause * * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. * Copyright (C) 1994, 1995, 1997 TooLs GmbH. * All rights reserved. * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by TooLs GmbH. * 4. The name of TooLs GmbH may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /*- * Written by Paul Popelka (paulp@uts.amdahl.com) * * You can do anything you want with this software, just don't say you wrote * it, and don't remove this notice. * * This software is provided "as is". * * The author supplies this software to be publicly redistributed on the * understanding that the author is not responsible for the correct * functioning of this software in any circumstances and is not liable for * any damages caused by this software. * * October 1992 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef MSDOSFS_DEBUG #include #endif static const char msdosfs_lock_msg[] = "fatlk"; /* Mount options that we support. */ static const char *msdosfs_opts[] = { "async", "noatime", "noclusterr", "noclusterw", "export", "force", "from", "sync", "cs_dos", "cs_local", "cs_win", "dirmask", "gid", "kiconv", "longname", "longnames", "mask", "shortname", "shortnames", "uid", "win95", "nowin95", NULL }; #if 1 /*def PC98*/ /* * XXX - The boot signature formatted by NEC PC-98 DOS looks like a * garbage or a random value :-{ * If you want to use that broken-signatured media, define the * following symbol even though PC/AT. * (ex. mount PC-98 DOS formatted FD on PC/AT) */ #define MSDOSFS_NOCHECKSIG #endif MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure"); static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table"); struct iconv_functions *msdosfs_iconv; static int update_mp(struct mount *mp, struct thread *td); static int mountmsdosfs(struct vnode *devvp, struct mount *mp); static void msdosfs_remount_ro(void *arg, int pending); static vfs_fhtovp_t msdosfs_fhtovp; static vfs_mount_t msdosfs_mount; static vfs_root_t msdosfs_root; static vfs_statfs_t msdosfs_statfs; static vfs_sync_t msdosfs_sync; static vfs_unmount_t msdosfs_unmount; /* Maximum length of a character set name (arbitrary). */ #define MAXCSLEN 64 static int update_mp(struct mount *mp, struct thread *td) { struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); void *dos, *win, *local; int error, v; if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) { if (msdosfs_iconv != NULL) { error = vfs_getopt(mp->mnt_optnew, "cs_win", &win, NULL); if (!error) error = vfs_getopt(mp->mnt_optnew, "cs_local", &local, NULL); if (!error) error = vfs_getopt(mp->mnt_optnew, "cs_dos", &dos, NULL); if (!error) { msdosfs_iconv->open(win, local, &pmp->pm_u2w); msdosfs_iconv->open(local, win, &pmp->pm_w2u); msdosfs_iconv->open(dos, local, &pmp->pm_u2d); msdosfs_iconv->open(local, dos, &pmp->pm_d2u); } if (error != 0) return (error); } else { pmp->pm_w2u = NULL; pmp->pm_u2w = NULL; pmp->pm_d2u = NULL; pmp->pm_u2d = NULL; } } if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1) pmp->pm_gid = v; if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1) pmp->pm_uid = v; if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1) pmp->pm_mask = v & ALLPERMS; if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1) pmp->pm_dirmask = v & ALLPERMS; vfs_flagopt(mp->mnt_optnew, "shortname", &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); vfs_flagopt(mp->mnt_optnew, "shortnames", &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); vfs_flagopt(mp->mnt_optnew, "longname", &pmp->pm_flags, MSDOSFSMNT_LONGNAME); vfs_flagopt(mp->mnt_optnew, "longnames", &pmp->pm_flags, MSDOSFSMNT_LONGNAME); vfs_flagopt(mp->mnt_optnew, "kiconv", &pmp->pm_flags, MSDOSFSMNT_KICONV); if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0) pmp->pm_flags |= MSDOSFSMNT_NOWIN95; else pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95; if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; else pmp->pm_flags |= MSDOSFSMNT_LONGNAME; return 0; } static int msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags) { struct msdosfs_args args; int error; if (data == NULL) return (EINVAL); error = copyin(data, &args, sizeof args); if (error) return (error); ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); ma = mount_arg(ma, "export", &args.export, sizeof(args.export)); ma = mount_argf(ma, "uid", "%d", args.uid); ma = mount_argf(ma, "gid", "%d", args.gid); ma = mount_argf(ma, "mask", "%d", args.mask); ma = mount_argf(ma, "dirmask", "%d", args.dirmask); ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); error = kernel_mount(ma, flags); return (error); } /* * mp - path - addr in user space of mount point (ie /usr or whatever) * data - addr in user space of mount params including the name of the block * special file to treat as a filesystem. */ static int msdosfs_mount(struct mount *mp) { struct vnode *devvp, *odevvp; /* vnode for blk device to mount */ struct thread *td; /* msdosfs specific mount control block */ struct msdosfsmount *pmp = NULL; struct nameidata ndp; int error, flags; accmode_t accmode; char *from; td = curthread; if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) return (EINVAL); /* * If updating, check whether changing from read-only to * read/write; if there is no device name, that's all we do. */ if (mp->mnt_flag & MNT_UPDATE) { pmp = VFSTOMSDOSFS(mp); if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { if ((error = vn_start_write(NULL, &mp, V_WAIT)) != 0) return (error); error = vfs_write_suspend_umnt(mp); if (error != 0) return (error); flags = WRITECLOSE; if (mp->mnt_flag & MNT_FORCE) flags |= FORCECLOSE; error = vflush(mp, 0, flags, td); if (error != 0) { vfs_write_resume(mp, 0); return (error); } /* * Now the volume is clean. Mark it so while the * device is still rw. */ error = markvoldirty(pmp, 0); if (error != 0) { vfs_write_resume(mp, 0); (void)markvoldirty(pmp, 1); return (error); } /* Downgrade the device from rw to ro. */ g_topology_lock(); error = g_access(pmp->pm_cp, 0, -1, 0); g_topology_unlock(); if (error) { vfs_write_resume(mp, 0); (void)markvoldirty(pmp, 1); return (error); } /* * Backing out after an error was painful in the * above. Now we are committed to succeeding. */ pmp->pm_fmod = 0; pmp->pm_flags |= MSDOSFSMNT_RONLY; MNT_ILOCK(mp); mp->mnt_flag |= MNT_RDONLY; MNT_IUNLOCK(mp); vfs_write_resume(mp, 0); } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { /* * If upgrade to read-write by non-root, then verify * that user has necessary permissions on the device. */ odevvp = pmp->pm_odevvp; vn_lock(odevvp, LK_EXCLUSIVE | LK_RETRY); error = VOP_ACCESS(odevvp, VREAD | VWRITE, td->td_ucred, td); if (error) error = priv_check(td, PRIV_VFS_MOUNT_PERM); if (error) { VOP_UNLOCK(odevvp); return (error); } VOP_UNLOCK(odevvp); g_topology_lock(); error = g_access(pmp->pm_cp, 0, 1, 0); g_topology_unlock(); if (error) return (error); /* Now that the volume is modifiable, mark it dirty. */ error = markvoldirty_upgrade(pmp, true, true); if (error) { /* * If dirtying the superblock failed, drop GEOM * 'w' refs (we're still RO). */ g_topology_lock(); (void)g_access(pmp->pm_cp, 0, -1, 0); g_topology_unlock(); return (error); } pmp->pm_fmod = 1; pmp->pm_flags &= ~MSDOSFSMNT_RONLY; MNT_ILOCK(mp); mp->mnt_flag &= ~MNT_RDONLY; MNT_IUNLOCK(mp); } /* * Avoid namei() below. The "from" option is not set. * Update of the devvp is pointless for this case. */ if ((pmp->pm_flags & MSDOSFS_ERR_RO) != 0) return (0); } /* * Not an update, or updating the name: look up the name * and verify that it refers to a sensible disk device. */ if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) return (EINVAL); NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from); error = namei(&ndp); if (error) return (error); devvp = ndp.ni_vp; NDFREE_PNBUF(&ndp); if (!vn_isdisk_error(devvp, &error)) { vput(devvp); return (error); } /* * If mount by non-root, then verify that user has necessary * permissions on the device. */ accmode = VREAD; if ((mp->mnt_flag & MNT_RDONLY) == 0) accmode |= VWRITE; error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); if (error) error = priv_check(td, PRIV_VFS_MOUNT_PERM); if (error) { vput(devvp); return (error); } if ((mp->mnt_flag & MNT_UPDATE) == 0) { error = mountmsdosfs(devvp, mp); #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ pmp = VFSTOMSDOSFS(mp); #endif } else { vput(devvp); if (devvp != pmp->pm_odevvp) return (EINVAL); /* XXX needs translation */ } if (error) { vrele(devvp); return (error); } error = update_mp(mp, td); if (error) { if ((mp->mnt_flag & MNT_UPDATE) == 0) msdosfs_unmount(mp, MNT_FORCE); return error; } vfs_mountedfrom(mp, from); #ifdef MSDOSFS_DEBUG printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); #endif return (0); } /* * The FAT12 and FAT16 file systems use a limited size root directory that * can be created with 1 to 65535 entries for files, directories, or a disk * label (but DOS or Windows creates at most 512 root directory entries). * This function calculates the number of free root directory entries by * counting the non-deleted entries (not starting with 0xE5) and by adding * the amount of never used entries (with the position indicated by an * entry that starts with 0x00). */ static int rootdir_free(struct msdosfsmount* pmp) { struct buf *bp; struct direntry *dep; u_long readsize; int dirclu; int diridx; int dirmax; int dirleft; int ffree; dirclu = pmp->pm_rootdirblk; /* * The msdosfs code ignores pm_RootDirEnts and uses pm_rootdirsize * (measured in DEV_BSIZE) to prevent excess root dir allocations. */ dirleft = howmany(pmp->pm_rootdirsize * DEV_BSIZE, sizeof(struct direntry)); /* Read in chunks of default maximum root directory size */ readsize = 512 * sizeof(struct direntry); #ifdef MSDOSFS_DEBUG printf("rootdir_free: blkpersec=%lu fatblksize=%lu dirsize=%lu " "firstclu=%lu dirclu=%d entries=%d rootdirsize=%lu " "bytespersector=%hu bytepercluster=%lu\n", pmp->pm_BlkPerSec, pmp->pm_fatblocksize, readsize, pmp->pm_firstcluster, dirclu, dirleft, pmp->pm_rootdirsize, pmp->pm_BytesPerSec, pmp->pm_bpcluster); #endif ffree = dirleft; while (dirleft > 0 && ffree > 0) { if (readsize > dirleft * sizeof(struct direntry)) readsize = dirleft * sizeof(struct direntry); #ifdef MSDOSFS_DEBUG printf("rootdir_free: dirclu=%d dirleft=%d readsize=%lu\n", dirclu, dirleft, readsize); #endif if (bread(pmp->pm_devvp, dirclu, readsize, NOCRED, &bp) != 0) { printf("rootdir_free: read error\n"); if (bp != NULL) brelse(bp); return (-1); } dirmax = readsize / sizeof(struct direntry); for (diridx = 0; diridx < dirmax && dirleft > 0; diridx++, dirleft--) { dep = (struct direntry*)bp->b_data + diridx; #ifdef MSDOSFS_DEBUG if (dep->deName[0] == SLOT_DELETED) printf("rootdir_free: idx=%d \n", diridx); else if (dep->deName[0] == SLOT_EMPTY) printf("rootdir_free: idx=%d \n", diridx); else if (dep->deAttributes == ATTR_WIN95) printf("rootdir_free: idx=%d \n", diridx, (dep->deName[0] & 0x1f) + 1); else if (dep->deAttributes & ATTR_VOLUME) printf("rootdir_free: idx=%d label='%11.11s'\n", diridx, dep->deName); else if (dep->deAttributes & ATTR_DIRECTORY) printf("rootdir_free: idx=%d dir='%11.11s'\n", diridx, dep->deName); else printf("rootdir_free: idx=%d file='%11.11s'\n", diridx, dep->deName); #endif if (dep->deName[0] == SLOT_EMPTY) dirleft = 0; else if (dep->deName[0] != SLOT_DELETED) ffree--; } brelse(bp); bp = NULL; dirclu += readsize / DEV_BSIZE; } return (ffree); } static int mountmsdosfs(struct vnode *odevvp, struct mount *mp) { struct msdosfsmount *pmp; struct buf *bp; struct cdev *dev; struct vnode *devvp; union bootsector *bsp; struct byte_bpb33 *b33; struct byte_bpb50 *b50; struct byte_bpb710 *b710; uint8_t SecPerClust; u_long clusters; int ronly, error; struct g_consumer *cp; struct bufobj *bo; bp = NULL; /* This and pmp both used in error_exit. */ pmp = NULL; ronly = (mp->mnt_flag & MNT_RDONLY) != 0; devvp = mntfs_allocvp(mp, odevvp); dev = devvp->v_rdev; if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0, (uintptr_t)mp) == 0) { mntfs_freevp(devvp); return (EBUSY); } g_topology_lock(); error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); g_topology_unlock(); if (error != 0) { atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); mntfs_freevp(devvp); return (error); } dev_ref(dev); bo = &devvp->v_bufobj; BO_LOCK(&odevvp->v_bufobj); odevvp->v_bufobj.bo_flag |= BO_NOBUFS; BO_UNLOCK(&odevvp->v_bufobj); VOP_UNLOCK(devvp); if (dev->si_iosize_max != 0) mp->mnt_iosize_max = dev->si_iosize_max; if (mp->mnt_iosize_max > maxphys) mp->mnt_iosize_max = maxphys; /* * Read the boot sector of the filesystem, and then check the * boot signature. If not a dos boot sector then error out. * * NOTE: 8192 is a magic size that works for ffs. */ error = bread(devvp, 0, 8192, NOCRED, &bp); if (error) goto error_exit; bp->b_flags |= B_AGE; bsp = (union bootsector *)bp->b_data; b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; #ifndef MSDOSFS_NOCHECKSIG if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { error = EINVAL; goto error_exit; } #endif pmp = malloc(sizeof(*pmp), M_MSDOSFSMNT, M_WAITOK | M_ZERO); pmp->pm_mountp = mp; pmp->pm_cp = cp; pmp->pm_bo = bo; lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); lockinit(&pmp->pm_checkpath_lock, 0, "msdoscp", 0, 0); TASK_INIT(&pmp->pm_rw2ro_task, 0, msdosfs_remount_ro, pmp); /* * Initialize ownerships and permissions, since nothing else will * initialize them iff we are mounting root. */ pmp->pm_uid = UID_ROOT; pmp->pm_gid = GID_WHEEL; pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; /* * Compute several useful quantities from the bpb in the * bootsector. Copy in the dos 5 variant of the bpb then fix up * the fields that are different between dos 5 and dos 3.3. */ SecPerClust = b50->bpbSecPerClust; pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); if (pmp->pm_BytesPerSec < DEV_BSIZE) { error = EINVAL; goto error_exit; } pmp->pm_ResSectors = getushort(b50->bpbResSectors); pmp->pm_FATs = b50->bpbFATs; pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); pmp->pm_Sectors = getushort(b50->bpbSectors); pmp->pm_FATsecs = getushort(b50->bpbFATsecs); pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); pmp->pm_Heads = getushort(b50->bpbHeads); pmp->pm_Media = b50->bpbMedia; /* calculate the ratio of sector size to DEV_BSIZE */ pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; /* * We don't check pm_Heads nor pm_SecPerTrack, because * these may not be set for EFI file systems. We don't * use these anyway, so we're unaffected if they are * invalid. */ if (pmp->pm_BytesPerSec == 0 || SecPerClust == 0) { error = EINVAL; goto error_exit; } if (pmp->pm_Sectors == 0) { pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); } else { pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); pmp->pm_HugeSectors = pmp->pm_Sectors; } if (pmp->pm_RootDirEnts == 0) { if (pmp->pm_FATsecs != 0 || getushort(b710->bpbFSVers) != 0) { error = EINVAL; #ifdef MSDOSFS_DEBUG printf("mountmsdosfs(): bad FAT32 filesystem\n"); #endif goto error_exit; } pmp->pm_fatmask = FAT32_MASK; pmp->pm_fatmult = 4; pmp->pm_fatdiv = 1; pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); if ((getushort(b710->bpbExtFlags) & FATMIRROR) != 0) pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; else pmp->pm_flags |= MSDOSFS_FATMIRROR; } else pmp->pm_flags |= MSDOSFS_FATMIRROR; /* * Check a few values (could do some more): * - logical sector size: power of 2, >= block size * - sectors per cluster: power of 2, >= 1 * - number of sectors: >= 1, <= size of partition * - number of FAT sectors: >= 1 */ if (SecPerClust == 0 || (SecPerClust & (SecPerClust - 1)) != 0 || pmp->pm_BytesPerSec < DEV_BSIZE || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) != 0 || pmp->pm_HugeSectors == 0 || pmp->pm_FATsecs == 0 || SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) { error = EINVAL; goto error_exit; } if ((off_t)pmp->pm_HugeSectors * pmp->pm_BytesPerSec < pmp->pm_HugeSectors /* overflow */ || (off_t)pmp->pm_HugeSectors * pmp->pm_BytesPerSec > cp->provider->mediasize /* past end of vol */) { error = EINVAL; goto error_exit; } pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ pmp->pm_FATsecs *= pmp->pm_BlkPerSec; SecPerClust *= pmp->pm_BlkPerSec; pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; if (FAT32(pmp)) { pmp->pm_rootdirblk = getulong(b710->bpbRootClust); pmp->pm_firstcluster = pmp->pm_fatblk + pmp->pm_FATs * pmp->pm_FATsecs; pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; } else { pmp->pm_rootdirblk = pmp->pm_fatblk + pmp->pm_FATs * pmp->pm_FATsecs; pmp->pm_rootdirsize = howmany(pmp->pm_RootDirEnts * sizeof(struct direntry), DEV_BSIZE); /* in blocks */ pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; } if (pmp->pm_HugeSectors <= pmp->pm_firstcluster) { error = EINVAL; goto error_exit; } pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / SecPerClust + 1; - pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ + pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; if (pmp->pm_fatmask == 0) { - if (pmp->pm_maxcluster <= ((CLUST_RSRVD - CLUST_FIRST) & - FAT12_MASK)) { + /* + * The last 10 (or 16?) clusters are reserved and must not + * be allocated for data. + */ + if (pmp->pm_maxcluster < (CLUST_RSRVD & FAT12_MASK)) { /* * This will usually be a floppy disk. This size makes * sure that one FAT entry will not be split across * multiple blocks. */ pmp->pm_fatmask = FAT12_MASK; pmp->pm_fatmult = 3; pmp->pm_fatdiv = 2; } else { pmp->pm_fatmask = FAT16_MASK; pmp->pm_fatmult = 2; pmp->pm_fatdiv = 1; } } - clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; + clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv ; if (pmp->pm_maxcluster >= clusters) { #ifdef MSDOSFS_DEBUG printf("Warning: number of clusters (%ld) exceeds FAT " - "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); + "capacity (%ld)\n", pmp->pm_maxcluster - 1, clusters); #endif pmp->pm_maxcluster = clusters - 1; } if (FAT12(pmp)) pmp->pm_fatblocksize = 3 * 512; else pmp->pm_fatblocksize = PAGE_SIZE; pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, pmp->pm_BytesPerSec); pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; /* * Compute mask and shift value for isolating cluster relative byte * offsets and cluster numbers from a file offset. */ pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; pmp->pm_crbomask = pmp->pm_bpcluster - 1; pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; /* * Check for valid cluster size * must be a power of 2 */ if ((pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) != 0) { error = EINVAL; goto error_exit; } /* * Release the bootsector buffer. */ brelse(bp); bp = NULL; /* * Check the fsinfo sector if we have one. Silently fix up our * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) * or too large. Ignore fp->fsinfree for now, since we need to * read the entire FAT anyway to fill the inuse map. */ if (pmp->pm_fsinfo) { struct fsinfo *fp; if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, NOCRED, &bp)) != 0) goto error_exit; fp = (struct fsinfo *)bp->b_data; if (!bcmp(fp->fsisig1, "RRaA", 4) && !bcmp(fp->fsisig2, "rrAa", 4) && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { pmp->pm_nxtfree = getulong(fp->fsinxtfree); if (pmp->pm_nxtfree > pmp->pm_maxcluster) pmp->pm_nxtfree = CLUST_FIRST; } else pmp->pm_fsinfo = 0; brelse(bp); bp = NULL; } /* * Finish initializing pmp->pm_nxtfree (just in case the first few * sectors aren't properly reserved in the FAT). This completes * the fixup for fp->fsinxtfree, and fixes up the zero-initialized * value if there is no fsinfo. We will use pmp->pm_nxtfree * internally even if there is no fsinfo. */ if (pmp->pm_nxtfree < CLUST_FIRST) pmp->pm_nxtfree = CLUST_FIRST; /* * Allocate memory for the bitmap of allocated clusters, and then * fill it in. */ pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) * sizeof(*pmp->pm_inusemap), M_MSDOSFSFAT, M_WAITOK); /* * fillinusemap() needs pm_devvp. */ pmp->pm_devvp = devvp; pmp->pm_odevvp = odevvp; pmp->pm_dev = dev; /* * Have the inuse map filled in. */ MSDOSFS_LOCK_MP(pmp); error = fillinusemap(pmp); MSDOSFS_UNLOCK_MP(pmp); if (error != 0) goto error_exit; /* * If they want FAT updates to be synchronous then let them suffer * the performance degradation in exchange for the on disk copy of * the FAT being correct just about all the time. I suppose this * would be a good thing to turn on if the kernel is still flakey. */ if (mp->mnt_flag & MNT_SYNCHRONOUS) pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; /* * Finish up. */ if (ronly) pmp->pm_flags |= MSDOSFSMNT_RONLY; else { if ((error = markvoldirty(pmp, 1)) != 0) goto error_exit; pmp->pm_fmod = 1; } if (FAT32(pmp)) { pmp->pm_rootdirfree = 0; } else { pmp->pm_rootdirfree = rootdir_free(pmp); if (pmp->pm_rootdirfree < 0) goto error_exit; } mp->mnt_data = pmp; mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; MNT_ILOCK(mp); mp->mnt_flag |= MNT_LOCAL; mp->mnt_kern_flag |= MNTK_USES_BCACHE | MNTK_NO_IOPF; MNT_IUNLOCK(mp); return (0); error_exit: if (bp != NULL) brelse(bp); if (cp != NULL) { g_topology_lock(); g_vfs_close(cp); g_topology_unlock(); } if (pmp != NULL) { lockdestroy(&pmp->pm_fatlock); lockdestroy(&pmp->pm_checkpath_lock); free(pmp->pm_inusemap, M_MSDOSFSFAT); free(pmp, M_MSDOSFSMNT); mp->mnt_data = NULL; } BO_LOCK(&odevvp->v_bufobj); odevvp->v_bufobj.bo_flag &= ~BO_NOBUFS; BO_UNLOCK(&odevvp->v_bufobj); atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); mntfs_freevp(devvp); dev_rel(dev); return (error); } /* * Unmount the filesystem described by mp. */ static int msdosfs_unmount(struct mount *mp, int mntflags) { struct msdosfsmount *pmp; int error, flags; bool susp; error = flags = 0; pmp = VFSTOMSDOSFS(mp); susp = (pmp->pm_flags & MSDOSFSMNT_RONLY) == 0; if (susp) { error = vfs_write_suspend_umnt(mp); if (error != 0) return (error); } if ((mntflags & MNT_FORCE) != 0) flags |= FORCECLOSE; error = vflush(mp, 0, flags, curthread); if (error != 0 && error != ENXIO) { if (susp) vfs_write_resume(mp, VR_START_WRITE); return (error); } if (susp) { error = markvoldirty(pmp, 0); if (error != 0 && error != ENXIO) { if (susp) vfs_write_resume(mp, VR_START_WRITE); (void)markvoldirty(pmp, 1); return (error); } } if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { if (pmp->pm_w2u) msdosfs_iconv->close(pmp->pm_w2u); if (pmp->pm_u2w) msdosfs_iconv->close(pmp->pm_u2w); if (pmp->pm_d2u) msdosfs_iconv->close(pmp->pm_d2u); if (pmp->pm_u2d) msdosfs_iconv->close(pmp->pm_u2d); } #ifdef MSDOSFS_DEBUG { struct vnode *vp = pmp->pm_devvp; struct bufobj *bo; bo = &vp->v_bufobj; BO_LOCK(bo); VI_LOCK(vp); vn_printf(vp, "msdosfs_umount(): just before calling VOP_CLOSE()\n"); printf("freef %p, freeb %p, mount %p\n", TAILQ_NEXT(vp, v_vnodelist), vp->v_vnodelist.tqe_prev, vp->v_mount); printf("cleanblkhd %p, dirtyblkhd %p, numoutput %d, type %d\n", TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), vp->v_bufobj.bo_numoutput, vp->v_type); VI_UNLOCK(vp); BO_UNLOCK(bo); } #endif if (susp) vfs_write_resume(mp, VR_START_WRITE); vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); g_topology_lock(); g_vfs_close(pmp->pm_cp); g_topology_unlock(); BO_LOCK(&pmp->pm_odevvp->v_bufobj); pmp->pm_odevvp->v_bufobj.bo_flag &= ~BO_NOBUFS; BO_UNLOCK(&pmp->pm_odevvp->v_bufobj); atomic_store_rel_ptr((uintptr_t *)&pmp->pm_dev->si_mountpt, 0); mntfs_freevp(pmp->pm_devvp); vrele(pmp->pm_odevvp); dev_rel(pmp->pm_dev); free(pmp->pm_inusemap, M_MSDOSFSFAT); lockdestroy(&pmp->pm_fatlock); lockdestroy(&pmp->pm_checkpath_lock); free(pmp, M_MSDOSFSMNT); mp->mnt_data = NULL; return (error); } static void msdosfs_remount_ro(void *arg, int pending) { struct msdosfsmount *pmp; int error; pmp = arg; MSDOSFS_LOCK_MP(pmp); if ((pmp->pm_flags & MSDOSFS_ERR_RO) != 0) { while ((pmp->pm_flags & MSDOSFS_ERR_RO) != 0) msleep(&pmp->pm_flags, &pmp->pm_fatlock, PVFS, "msdoserrro", hz); } else if ((pmp->pm_mountp->mnt_flag & MNT_RDONLY) == 0) { pmp->pm_flags |= MSDOSFS_ERR_RO; MSDOSFS_UNLOCK_MP(pmp); printf("%s: remounting read-only due to corruption\n", pmp->pm_mountp->mnt_stat.f_mntfromname); error = vfs_remount_ro(pmp->pm_mountp); if (error != 0) printf("%s: remounting read-only failed: error %d\n", pmp->pm_mountp->mnt_stat.f_mntfromname, error); else printf("remounted %s read-only\n", pmp->pm_mountp->mnt_stat.f_mntfromname); MSDOSFS_LOCK_MP(pmp); pmp->pm_flags &= ~MSDOSFS_ERR_RO; wakeup(&pmp->pm_flags); } MSDOSFS_UNLOCK_MP(pmp); vfs_unbusy(pmp->pm_mountp); } void msdosfs_integrity_error(struct msdosfsmount *pmp) { int error; error = vfs_busy(pmp->pm_mountp, MBF_NOWAIT); if (error == 0) taskqueue_enqueue(taskqueue_thread, &pmp->pm_rw2ro_task); else printf("%s: integrity error busying failed, error %d\n", pmp->pm_mountp->mnt_stat.f_mntfromname, error); } static int msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) { struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); struct denode *ndep; int error; #ifdef MSDOSFS_DEBUG printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); #endif error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, LK_EXCLUSIVE, &ndep); if (error) return (error); *vpp = DETOV(ndep); return (0); } static int msdosfs_statfs(struct mount *mp, struct statfs *sbp) { struct msdosfsmount *pmp; pmp = VFSTOMSDOSFS(mp); sbp->f_bsize = pmp->pm_bpcluster; sbp->f_iosize = pmp->pm_bpcluster; - sbp->f_blocks = pmp->pm_maxcluster + 1; + sbp->f_blocks = pmp->pm_maxcluster - CLUST_FIRST + 1; sbp->f_bfree = pmp->pm_freeclustercount; sbp->f_bavail = pmp->pm_freeclustercount; sbp->f_files = howmany(pmp->pm_rootdirsize * DEV_BSIZE, sizeof(struct direntry)); sbp->f_ffree = pmp->pm_rootdirfree; return (0); } /* * If we have an FSInfo block, update it. */ static int msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor) { struct fsinfo *fp; struct buf *bp; int error; MSDOSFS_LOCK_MP(pmp); if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) { error = 0; goto unlock; } error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, NOCRED, &bp); if (error != 0) { goto unlock; } fp = (struct fsinfo *)bp->b_data; putulong(fp->fsinfree, pmp->pm_freeclustercount); putulong(fp->fsinxtfree, pmp->pm_nxtfree); pmp->pm_flags &= ~MSDOSFS_FSIMOD; if (waitfor == MNT_WAIT) error = bwrite(bp); else bawrite(bp); unlock: MSDOSFS_UNLOCK_MP(pmp); return (error); } static int msdosfs_sync(struct mount *mp, int waitfor) { struct vnode *vp, *nvp; struct thread *td; struct denode *dep; struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); int error, allerror = 0; td = curthread; /* * If we ever switch to not updating all of the FATs all the time, * this would be the place to update them from the first one. */ if (pmp->pm_fmod != 0) { if (pmp->pm_flags & MSDOSFSMNT_RONLY) panic("msdosfs_sync: rofs mod"); else { /* update FATs here */ } } /* * Write back each (modified) denode. */ loop: MNT_VNODE_FOREACH_ALL(vp, mp, nvp) { if (vp->v_type == VNON) { VI_UNLOCK(vp); continue; } dep = VTODE(vp); if ((dep->de_flag & (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && (vp->v_bufobj.bo_dirty.bv_cnt == 0 || waitfor == MNT_LAZY)) { VI_UNLOCK(vp); continue; } error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK); if (error) { if (error == ENOENT) { MNT_VNODE_FOREACH_ALL_ABORT(mp, nvp); goto loop; } continue; } error = VOP_FSYNC(vp, waitfor, td); if (error) allerror = error; vput(vp); } /* * Flush filesystem control info. */ if (waitfor != MNT_LAZY) { vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); if (error) allerror = error; VOP_UNLOCK(pmp->pm_devvp); } error = msdosfs_fsiflush(pmp, waitfor); if (error != 0) allerror = error; if (allerror == 0 && waitfor == MNT_SUSPEND) { MNT_ILOCK(mp); mp->mnt_kern_flag |= MNTK_SUSPEND2 | MNTK_SUSPENDED; MNT_IUNLOCK(mp); } return (allerror); } static int msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) { struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); struct defid *defhp = (struct defid *) fhp; struct denode *dep; int error; error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, LK_EXCLUSIVE, &dep); if (error) { *vpp = NULLVP; return (error); } *vpp = DETOV(dep); vnode_create_vobject(*vpp, dep->de_FileSize, curthread); return (0); } static struct vfsops msdosfs_vfsops = { .vfs_fhtovp = msdosfs_fhtovp, .vfs_mount = msdosfs_mount, .vfs_cmount = msdosfs_cmount, .vfs_root = msdosfs_root, .vfs_statfs = msdosfs_statfs, .vfs_sync = msdosfs_sync, .vfs_unmount = msdosfs_unmount, }; VFS_SET(msdosfs_vfsops, msdosfs, 0); MODULE_VERSION(msdosfs, 1); diff --git a/sys/fs/msdosfs/msdosfs_vnops.c b/sys/fs/msdosfs/msdosfs_vnops.c index f095a4abea62..bc47f9dde574 100644 --- a/sys/fs/msdosfs/msdosfs_vnops.c +++ b/sys/fs/msdosfs/msdosfs_vnops.c @@ -1,1995 +1,1998 @@ /* $FreeBSD$ */ /* $NetBSD: msdosfs_vnops.c,v 1.68 1998/02/10 14:10:04 mrg Exp $ */ /*- * SPDX-License-Identifier: BSD-4-Clause * * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. * Copyright (C) 1994, 1995, 1997 TooLs GmbH. * All rights reserved. * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by TooLs GmbH. * 4. The name of TooLs GmbH may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /*- * Written by Paul Popelka (paulp@uts.amdahl.com) * * You can do anything you want with this software, just don't say you wrote * it, and don't remove this notice. * * This software is provided "as is". * * The author supplies this software to be publicly redistributed on the * understanding that the author is not responsible for the correct * functioning of this software in any circumstances and is not liable for * any damages caused by this software. * * October 1992 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Prototypes for MSDOSFS vnode operations */ static vop_create_t msdosfs_create; static vop_mknod_t msdosfs_mknod; static vop_open_t msdosfs_open; static vop_close_t msdosfs_close; static vop_access_t msdosfs_access; static vop_getattr_t msdosfs_getattr; static vop_setattr_t msdosfs_setattr; static vop_read_t msdosfs_read; static vop_write_t msdosfs_write; static vop_fsync_t msdosfs_fsync; static vop_remove_t msdosfs_remove; static vop_link_t msdosfs_link; static vop_rename_t msdosfs_rename; static vop_mkdir_t msdosfs_mkdir; static vop_rmdir_t msdosfs_rmdir; static vop_symlink_t msdosfs_symlink; static vop_readdir_t msdosfs_readdir; static vop_bmap_t msdosfs_bmap; static vop_getpages_t msdosfs_getpages; static vop_strategy_t msdosfs_strategy; static vop_print_t msdosfs_print; static vop_pathconf_t msdosfs_pathconf; static vop_vptofh_t msdosfs_vptofh; /* * Some general notes: * * In the ufs filesystem the inodes, superblocks, and indirect blocks are * read/written using the vnode for the filesystem. Blocks that represent * the contents of a file are read/written using the vnode for the file * (including directories when they are read/written as files). This * presents problems for the dos filesystem because data that should be in * an inode (if dos had them) resides in the directory itself. Since we * must update directory entries without the benefit of having the vnode * for the directory we must use the vnode for the filesystem. This means * that when a directory is actually read/written (via read, write, or * readdir, or seek) we must use the vnode for the filesystem instead of * the vnode for the directory as would happen in ufs. This is to insure we * retrieve the correct block from the buffer cache since the hash value is * based upon the vnode address and the desired block number. */ /* * Create a regular file. On entry the directory to contain the file being * created is locked. We must release before we return. We must also free * the pathname buffer pointed at by cnp->cn_pnbuf, always on error. */ static int msdosfs_create(struct vop_create_args *ap) { struct componentname *cnp = ap->a_cnp; struct denode ndirent; struct denode *dep; struct denode *pdep = VTODE(ap->a_dvp); struct timespec ts; int error; #ifdef MSDOSFS_DEBUG printf("msdosfs_create(cnp %p, vap %p\n", cnp, ap->a_vap); #endif /* * If this is the root directory and there is no space left we * can't do anything. This is because the root directory can not * change size. */ if (pdep->de_StartCluster == MSDOSFSROOT && pdep->de_fndoffset >= pdep->de_FileSize) { error = ENOSPC; goto bad; } /* * Create a directory entry for the file, then call createde() to * have it installed. NOTE: DOS files are always executable. We * use the absence of the owner write bit to make the file * readonly. */ memset(&ndirent, 0, sizeof(ndirent)); error = uniqdosname(pdep, cnp, ndirent.de_Name); if (error) goto bad; ndirent.de_Attributes = ATTR_ARCHIVE; ndirent.de_LowerCase = 0; ndirent.de_StartCluster = 0; ndirent.de_FileSize = 0; ndirent.de_pmp = pdep->de_pmp; ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE; vfs_timestamp(&ts); DETIMES(&ndirent, &ts, &ts, &ts); error = createde(&ndirent, pdep, &dep, cnp); if (error) goto bad; *ap->a_vpp = DETOV(dep); if ((cnp->cn_flags & MAKEENTRY) != 0) cache_enter(ap->a_dvp, *ap->a_vpp, cnp); return (0); bad: return (error); } static int msdosfs_mknod(struct vop_mknod_args *ap) { return (EINVAL); } static int msdosfs_open(struct vop_open_args *ap) { struct denode *dep = VTODE(ap->a_vp); vnode_create_vobject(ap->a_vp, dep->de_FileSize, ap->a_td); return 0; } static int msdosfs_close(struct vop_close_args *ap) { struct vnode *vp = ap->a_vp; struct denode *dep = VTODE(vp); struct timespec ts; VI_LOCK(vp); if (vp->v_usecount > 1) { vfs_timestamp(&ts); DETIMES(dep, &ts, &ts, &ts); } VI_UNLOCK(vp); return 0; } static int msdosfs_access(struct vop_access_args *ap) { struct vnode *vp = ap->a_vp; struct denode *dep = VTODE(ap->a_vp); struct msdosfsmount *pmp = dep->de_pmp; mode_t file_mode; accmode_t accmode = ap->a_accmode; file_mode = S_IRWXU|S_IRWXG|S_IRWXO; file_mode &= (vp->v_type == VDIR ? pmp->pm_dirmask : pmp->pm_mask); /* * Disallow writing to directories and regular files if the * filesystem is read-only. */ if (accmode & VWRITE) { switch (vp->v_type) { case VREG: case VDIR: if (vp->v_mount->mnt_flag & MNT_RDONLY) return (EROFS); break; default: break; } } return (vaccess(vp->v_type, file_mode, pmp->pm_uid, pmp->pm_gid, ap->a_accmode, ap->a_cred)); } static int msdosfs_getattr(struct vop_getattr_args *ap) { struct denode *dep = VTODE(ap->a_vp); struct msdosfsmount *pmp = dep->de_pmp; struct vattr *vap = ap->a_vap; mode_t mode; struct timespec ts; u_long dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry); uint64_t fileid; vfs_timestamp(&ts); DETIMES(dep, &ts, &ts, &ts); vap->va_fsid = dev2udev(pmp->pm_dev); /* * The following computation of the fileid must be the same as that * used in msdosfs_readdir() to compute d_fileno. If not, pwd * doesn't work. */ if (dep->de_Attributes & ATTR_DIRECTORY) { fileid = (uint64_t)cntobn(pmp, dep->de_StartCluster) * dirsperblk; if (dep->de_StartCluster == MSDOSFSROOT) fileid = 1; } else { fileid = (uint64_t)cntobn(pmp, dep->de_dirclust) * dirsperblk; if (dep->de_dirclust == MSDOSFSROOT) fileid = (uint64_t)roottobn(pmp, 0) * dirsperblk; fileid += (uoff_t)dep->de_diroffset / sizeof(struct direntry); } vap->va_fileid = fileid; mode = S_IRWXU|S_IRWXG|S_IRWXO; if (dep->de_Attributes & ATTR_READONLY) mode &= ~(S_IWUSR|S_IWGRP|S_IWOTH); vap->va_mode = mode & (ap->a_vp->v_type == VDIR ? pmp->pm_dirmask : pmp->pm_mask); vap->va_uid = pmp->pm_uid; vap->va_gid = pmp->pm_gid; vap->va_nlink = 1; vap->va_rdev = NODEV; vap->va_size = dep->de_FileSize; fattime2timespec(dep->de_MDate, dep->de_MTime, 0, 0, &vap->va_mtime); vap->va_ctime = vap->va_mtime; if (pmp->pm_flags & MSDOSFSMNT_LONGNAME) { fattime2timespec(dep->de_ADate, 0, 0, 0, &vap->va_atime); fattime2timespec(dep->de_CDate, dep->de_CTime, dep->de_CHun, 0, &vap->va_birthtime); } else { vap->va_atime = vap->va_mtime; vap->va_birthtime.tv_sec = -1; vap->va_birthtime.tv_nsec = 0; } vap->va_flags = 0; if (dep->de_Attributes & ATTR_ARCHIVE) vap->va_flags |= UF_ARCHIVE; if (dep->de_Attributes & ATTR_HIDDEN) vap->va_flags |= UF_HIDDEN; if (dep->de_Attributes & ATTR_READONLY) vap->va_flags |= UF_READONLY; if (dep->de_Attributes & ATTR_SYSTEM) vap->va_flags |= UF_SYSTEM; vap->va_gen = 0; vap->va_blocksize = pmp->pm_bpcluster; - vap->va_bytes = - (dep->de_FileSize + pmp->pm_crbomask) & ~pmp->pm_crbomask; + if (dep->de_StartCluster != MSDOSFSROOT) + vap->va_bytes = + (dep->de_FileSize + pmp->pm_crbomask) & ~pmp->pm_crbomask; + else + vap->va_bytes = 0; /* FAT12/FAT16 root dir in reserved area */ vap->va_type = ap->a_vp->v_type; vap->va_filerev = dep->de_modrev; return (0); } static int msdosfs_setattr(struct vop_setattr_args *ap) { struct vnode *vp = ap->a_vp; struct denode *dep = VTODE(ap->a_vp); struct msdosfsmount *pmp = dep->de_pmp; struct vattr *vap = ap->a_vap; struct ucred *cred = ap->a_cred; struct thread *td = curthread; int error = 0; #ifdef MSDOSFS_DEBUG printf("msdosfs_setattr(): vp %p, vap %p, cred %p\n", ap->a_vp, vap, cred); #endif /* * Check for unsettable attributes. */ if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) || (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) || (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) || (vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) { #ifdef MSDOSFS_DEBUG printf("msdosfs_setattr(): returning EINVAL\n"); printf(" va_type %d, va_nlink %llx, va_fsid %llx, va_fileid %llx\n", vap->va_type, (unsigned long long)vap->va_nlink, (unsigned long long)vap->va_fsid, (unsigned long long)vap->va_fileid); printf(" va_blocksize %lx, va_rdev %llx, va_bytes %llx, va_gen %lx\n", vap->va_blocksize, (unsigned long long)vap->va_rdev, (unsigned long long)vap->va_bytes, vap->va_gen); printf(" va_uid %x, va_gid %x\n", vap->va_uid, vap->va_gid); #endif return (EINVAL); } /* * We don't allow setting attributes on the root directory. * The special case for the root directory is because before * FAT32, the root directory didn't have an entry for itself * (and was otherwise special). With FAT32, the root * directory is not so special, but still doesn't have an * entry for itself. */ if (vp->v_vflag & VV_ROOT) return (EINVAL); if (vap->va_flags != VNOVAL) { if (vp->v_mount->mnt_flag & MNT_RDONLY) return (EROFS); if (cred->cr_uid != pmp->pm_uid) { error = priv_check_cred(cred, PRIV_VFS_ADMIN); if (error) return (error); } /* * We are very inconsistent about handling unsupported * attributes. We ignored the access time and the * read and execute bits. We were strict for the other * attributes. */ if (vap->va_flags & ~(UF_ARCHIVE | UF_HIDDEN | UF_READONLY | UF_SYSTEM)) return EOPNOTSUPP; if (vap->va_flags & UF_ARCHIVE) dep->de_Attributes |= ATTR_ARCHIVE; else dep->de_Attributes &= ~ATTR_ARCHIVE; if (vap->va_flags & UF_HIDDEN) dep->de_Attributes |= ATTR_HIDDEN; else dep->de_Attributes &= ~ATTR_HIDDEN; /* We don't allow changing the readonly bit on directories. */ if (vp->v_type != VDIR) { if (vap->va_flags & UF_READONLY) dep->de_Attributes |= ATTR_READONLY; else dep->de_Attributes &= ~ATTR_READONLY; } if (vap->va_flags & UF_SYSTEM) dep->de_Attributes |= ATTR_SYSTEM; else dep->de_Attributes &= ~ATTR_SYSTEM; dep->de_flag |= DE_MODIFIED; } if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) { uid_t uid; gid_t gid; if (vp->v_mount->mnt_flag & MNT_RDONLY) return (EROFS); uid = vap->va_uid; if (uid == (uid_t)VNOVAL) uid = pmp->pm_uid; gid = vap->va_gid; if (gid == (gid_t)VNOVAL) gid = pmp->pm_gid; if (cred->cr_uid != pmp->pm_uid || uid != pmp->pm_uid || (gid != pmp->pm_gid && !groupmember(gid, cred))) { error = priv_check_cred(cred, PRIV_VFS_CHOWN); if (error) return (error); } if (uid != pmp->pm_uid || gid != pmp->pm_gid) return EINVAL; } if (vap->va_size != VNOVAL) { switch (vp->v_type) { case VDIR: return (EISDIR); case VREG: /* * Truncation is only supported for regular files, * Disallow it if the filesystem is read-only. */ if (vp->v_mount->mnt_flag & MNT_RDONLY) return (EROFS); break; default: /* * According to POSIX, the result is unspecified * for file types other than regular files, * directories and shared memory objects. We * don't support any file types except regular * files and directories in this file system, so * this (default) case is unreachable and can do * anything. Keep falling through to detrunc() * for now. */ break; } error = vn_rlimit_trunc(vap->va_size, td); if (error != 0) return (error); error = detrunc(dep, vap->va_size, 0, cred); if (error) return error; } if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) { if (vp->v_mount->mnt_flag & MNT_RDONLY) return (EROFS); error = vn_utimes_perm(vp, vap, cred, td); if (error != 0) return (error); if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95) == 0 && vap->va_atime.tv_sec != VNOVAL) { dep->de_flag &= ~DE_ACCESS; timespec2fattime(&vap->va_atime, 0, &dep->de_ADate, NULL, NULL); } if (vap->va_mtime.tv_sec != VNOVAL) { dep->de_flag &= ~DE_UPDATE; timespec2fattime(&vap->va_mtime, 0, &dep->de_MDate, &dep->de_MTime, NULL); } /* * We don't set the archive bit when modifying the time of * a directory to emulate the Windows/DOS behavior. */ if (vp->v_type != VDIR) dep->de_Attributes |= ATTR_ARCHIVE; dep->de_flag |= DE_MODIFIED; } /* * DOS files only have the ability to have their writability * attribute set, so we use the owner write bit to set the readonly * attribute. */ if (vap->va_mode != (mode_t)VNOVAL) { if (vp->v_mount->mnt_flag & MNT_RDONLY) return (EROFS); if (cred->cr_uid != pmp->pm_uid) { error = priv_check_cred(cred, PRIV_VFS_ADMIN); if (error) return (error); } if (vp->v_type != VDIR) { /* We ignore the read and execute bits. */ if (vap->va_mode & S_IWUSR) dep->de_Attributes &= ~ATTR_READONLY; else dep->de_Attributes |= ATTR_READONLY; dep->de_Attributes |= ATTR_ARCHIVE; dep->de_flag |= DE_MODIFIED; } } return (deupdat(dep, 0)); } static int msdosfs_read(struct vop_read_args *ap) { int error = 0; int blsize; int isadir; ssize_t orig_resid; u_int n; u_long diff; u_long on; daddr_t lbn; daddr_t rablock; int rasize; int seqcount; struct buf *bp; struct vnode *vp = ap->a_vp; struct denode *dep = VTODE(vp); struct msdosfsmount *pmp = dep->de_pmp; struct uio *uio = ap->a_uio; /* * If they didn't ask for any data, then we are done. */ orig_resid = uio->uio_resid; if (orig_resid == 0) return (0); /* * The caller is supposed to ensure that * uio->uio_offset >= 0 and uio->uio_resid >= 0. * We don't need to check for large offsets as in ffs because * dep->de_FileSize <= MSDOSFS_FILESIZE_MAX < OFF_MAX, so large * offsets cannot cause overflow even in theory. */ seqcount = ap->a_ioflag >> IO_SEQSHIFT; isadir = dep->de_Attributes & ATTR_DIRECTORY; do { if (uio->uio_offset >= dep->de_FileSize) break; lbn = de_cluster(pmp, uio->uio_offset); rablock = lbn + 1; blsize = pmp->pm_bpcluster; on = uio->uio_offset & pmp->pm_crbomask; /* * If we are operating on a directory file then be sure to * do i/o with the vnode for the filesystem instead of the * vnode for the directory. */ if (isadir) { /* convert cluster # to block # */ error = pcbmap(dep, lbn, &lbn, 0, &blsize); if (error == E2BIG) { error = EINVAL; break; } else if (error) break; error = bread(pmp->pm_devvp, lbn, blsize, NOCRED, &bp); } else if (de_cn2off(pmp, rablock) >= dep->de_FileSize) { error = bread(vp, lbn, blsize, NOCRED, &bp); } else if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) { error = cluster_read(vp, dep->de_FileSize, lbn, blsize, NOCRED, on + uio->uio_resid, seqcount, 0, &bp); } else if (seqcount > 1) { rasize = blsize; error = breadn(vp, lbn, blsize, &rablock, &rasize, 1, NOCRED, &bp); } else { error = bread(vp, lbn, blsize, NOCRED, &bp); } if (error) { brelse(bp); break; } diff = pmp->pm_bpcluster - on; n = diff > uio->uio_resid ? uio->uio_resid : diff; diff = dep->de_FileSize - uio->uio_offset; if (diff < n) n = diff; diff = blsize - bp->b_resid; if (diff < n) n = diff; error = vn_io_fault_uiomove(bp->b_data + on, (int) n, uio); brelse(bp); } while (error == 0 && uio->uio_resid > 0 && n != 0); if (!isadir && (error == 0 || uio->uio_resid != orig_resid) && (vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) dep->de_flag |= DE_ACCESS; return (error); } /* * Write data to a file or directory. */ static int msdosfs_write(struct vop_write_args *ap) { int n; int croffset; ssize_t resid, r; u_long osize; int error = 0; u_long count; int seqcount; daddr_t bn, lastcn; struct buf *bp; int ioflag = ap->a_ioflag; struct uio *uio = ap->a_uio; struct vnode *vp = ap->a_vp; struct vnode *thisvp; struct denode *dep = VTODE(vp); struct msdosfsmount *pmp = dep->de_pmp; struct ucred *cred = ap->a_cred; #ifdef MSDOSFS_DEBUG printf("msdosfs_write(vp %p, uio %p, ioflag %x, cred %p\n", vp, uio, ioflag, cred); printf("msdosfs_write(): diroff %lu, dirclust %lu, startcluster %lu\n", dep->de_diroffset, dep->de_dirclust, dep->de_StartCluster); #endif switch (vp->v_type) { case VREG: if (ioflag & IO_APPEND) uio->uio_offset = dep->de_FileSize; thisvp = vp; break; case VDIR: return EISDIR; default: panic("msdosfs_write(): bad file type"); } /* * This is needed (unlike in ffs_write()) because we extend the * file outside of the loop but we don't want to extend the file * for writes of 0 bytes. */ if (uio->uio_resid == 0) return (0); /* * The caller is supposed to ensure that * uio->uio_offset >= 0 and uio->uio_resid >= 0. * * If they've exceeded their filesize limit, tell them about it. */ error = vn_rlimit_fsizex(vp, uio, MSDOSFS_FILESIZE_MAX, &r, uio->uio_td); if (error != 0) { vn_rlimit_fsizex_res(uio, r); return (error); } /* * If the offset we are starting the write at is beyond the end of * the file, then they've done a seek. Unix filesystems allow * files with holes in them, DOS doesn't so we must fill the hole * with zeroed blocks. */ if (uio->uio_offset > dep->de_FileSize) { error = deextend(dep, uio->uio_offset, cred); if (error != 0) { vn_rlimit_fsizex_res(uio, r); return (error); } } /* * Remember some values in case the write fails. */ resid = uio->uio_resid; osize = dep->de_FileSize; /* * If we write beyond the end of the file, extend it to its ultimate * size ahead of the time to hopefully get a contiguous area. */ if (uio->uio_offset + resid > osize) { count = de_clcount(pmp, uio->uio_offset + resid) - de_clcount(pmp, osize); error = extendfile(dep, count, NULL, NULL, 0); if (error && (error != ENOSPC || (ioflag & IO_UNIT))) goto errexit; lastcn = dep->de_fc[FC_LASTFC].fc_frcn; } else lastcn = de_clcount(pmp, osize) - 1; seqcount = ioflag >> IO_SEQSHIFT; do { if (de_cluster(pmp, uio->uio_offset) > lastcn) { error = ENOSPC; break; } croffset = uio->uio_offset & pmp->pm_crbomask; n = min(uio->uio_resid, pmp->pm_bpcluster - croffset); if (uio->uio_offset + n > dep->de_FileSize) { dep->de_FileSize = uio->uio_offset + n; /* The object size needs to be set before buffer is allocated */ vnode_pager_setsize(vp, dep->de_FileSize); } bn = de_cluster(pmp, uio->uio_offset); if ((uio->uio_offset & pmp->pm_crbomask) == 0 && (de_cluster(pmp, uio->uio_offset + uio->uio_resid) > de_cluster(pmp, uio->uio_offset) || uio->uio_offset + uio->uio_resid >= dep->de_FileSize)) { /* * If either the whole cluster gets written, * or we write the cluster from its start beyond EOF, * then no need to read data from disk. */ bp = getblk(thisvp, bn, pmp->pm_bpcluster, 0, 0, 0); /* * This call to vfs_bio_clrbuf() ensures that * even if vn_io_fault_uiomove() below faults, * garbage from the newly instantiated buffer * is not exposed to the userspace via mmap(). */ vfs_bio_clrbuf(bp); /* * Do the bmap now, since pcbmap needs buffers * for the FAT table. (see msdosfs_strategy) */ if (bp->b_blkno == bp->b_lblkno) { error = pcbmap(dep, bp->b_lblkno, &bn, 0, 0); if (error) bp->b_blkno = -1; else bp->b_blkno = bn; } if (bp->b_blkno == -1) { brelse(bp); if (!error) error = EIO; /* XXX */ break; } } else { /* * The block we need to write into exists, so read it in. */ error = bread(thisvp, bn, pmp->pm_bpcluster, cred, &bp); if (error) { break; } } /* * Should these vnode_pager_* functions be done on dir * files? */ /* * Copy the data from user space into the buf header. */ error = vn_io_fault_uiomove(bp->b_data + croffset, n, uio); if (error) { brelse(bp); break; } /* Prepare for clustered writes in some else clauses. */ if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERW) == 0) bp->b_flags |= B_CLUSTEROK; /* * If IO_SYNC, then each buffer is written synchronously. * Otherwise, if we have a severe page deficiency then * write the buffer asynchronously. Otherwise, if on a * cluster boundary then write the buffer asynchronously, * combining it with contiguous clusters if permitted and * possible, since we don't expect more writes into this * buffer soon. Otherwise, do a delayed write because we * expect more writes into this buffer soon. */ if (ioflag & IO_SYNC) (void)bwrite(bp); else if (vm_page_count_severe() || buf_dirty_count_severe()) bawrite(bp); else if (n + croffset == pmp->pm_bpcluster) { if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERW) == 0) cluster_write(vp, &dep->de_clusterw, bp, dep->de_FileSize, seqcount, 0); else bawrite(bp); } else bdwrite(bp); dep->de_flag |= DE_UPDATE; } while (error == 0 && uio->uio_resid > 0); /* * If the write failed and they want us to, truncate the file back * to the size it was before the write was attempted. */ errexit: if (error) { if (ioflag & IO_UNIT) { detrunc(dep, osize, ioflag & IO_SYNC, NOCRED); uio->uio_offset -= resid - uio->uio_resid; uio->uio_resid = resid; } else { detrunc(dep, dep->de_FileSize, ioflag & IO_SYNC, NOCRED); if (uio->uio_resid != resid) error = 0; } } else if (ioflag & IO_SYNC) error = deupdat(dep, 1); vn_rlimit_fsizex_res(uio, r); return (error); } /* * Flush the blocks of a file to disk. */ static int msdosfs_fsync(struct vop_fsync_args *ap) { struct vnode *devvp; int allerror, error; vop_stdfsync(ap); /* * If the syncing request comes from fsync(2), sync the entire * FAT and any other metadata that happens to be on devvp. We * need this mainly for the FAT. We write the FAT sloppily, and * syncing it all now is the best we can easily do to get all * directory entries associated with the file (not just the file) * fully synced. The other metadata includes critical metadata * for all directory entries, but only in the MNT_ASYNC case. We * will soon sync all metadata in the file's directory entry. * Non-critical metadata for associated directory entries only * gets synced accidentally, as in most file systems. */ if (ap->a_waitfor != MNT_NOWAIT) { devvp = VTODE(ap->a_vp)->de_pmp->pm_devvp; vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); allerror = VOP_FSYNC(devvp, MNT_WAIT, ap->a_td); VOP_UNLOCK(devvp); } else allerror = 0; error = deupdat(VTODE(ap->a_vp), ap->a_waitfor != MNT_NOWAIT); if (allerror == 0) allerror = error; return (allerror); } static int msdosfs_remove(struct vop_remove_args *ap) { struct denode *dep = VTODE(ap->a_vp); struct denode *ddep = VTODE(ap->a_dvp); int error; if (ap->a_vp->v_type == VDIR) error = EPERM; else error = removede(ddep, dep); #ifdef MSDOSFS_DEBUG printf("msdosfs_remove(), dep %p, v_usecount %d\n", dep, ap->a_vp->v_usecount); #endif return (error); } /* * DOS filesystems don't know what links are. */ static int msdosfs_link(struct vop_link_args *ap) { return (EOPNOTSUPP); } /* * Renames on files require moving the denode to a new hash queue since the * denode's location is used to compute which hash queue to put the file * in. Unless it is a rename in place. For example "mv a b". * * What follows is the basic algorithm: * * if (file move) { * if (dest file exists) { * remove dest file * } * if (dest and src in same directory) { * rewrite name in existing directory slot * } else { * write new entry in dest directory * update offset and dirclust in denode * move denode to new hash chain * clear old directory entry * } * } else { * directory move * if (dest directory exists) { * if (dest is not empty) { * return ENOTEMPTY * } * remove dest directory * } * if (dest and src in same directory) { * rewrite name in existing entry * } else { * be sure dest is not a child of src directory * write entry in dest directory * update "." and ".." in moved directory * clear old directory entry for moved directory * } * } * * On entry: * source's parent directory is unlocked * source file or directory is unlocked * destination's parent directory is locked * destination file or directory is locked if it exists * * On exit: * all denodes should be released */ static int msdosfs_rename(struct vop_rename_args *ap) { struct vnode *fdvp, *fvp, *tdvp, *tvp, *vp; struct componentname *fcnp, *tcnp; struct denode *fdip, *fip, *tdip, *tip, *nip; u_char toname[12], oldname[11]; u_long to_diroffset; bool checkpath_locked, doingdirectory, newparent; int error; u_long cn, pcl, blkoff; daddr_t bn, wait_scn, scn; struct msdosfsmount *pmp; struct direntry *dotdotp; struct buf *bp; tdvp = ap->a_tdvp; fvp = ap->a_fvp; fdvp = ap->a_fdvp; tvp = ap->a_tvp; tcnp = ap->a_tcnp; fcnp = ap->a_fcnp; pmp = VFSTOMSDOSFS(fdvp->v_mount); /* * Check for cross-device rename. */ if (fvp->v_mount != tdvp->v_mount || (tvp != NULL && fvp->v_mount != tvp->v_mount)) { error = EXDEV; goto abortit; } /* * If source and dest are the same, do nothing. */ if (tvp == fvp) { error = 0; goto abortit; } /* * When the target exists, both the directory * and target vnodes are passed locked. */ VOP_UNLOCK(tdvp); if (tvp != NULL && tvp != tdvp) VOP_UNLOCK(tvp); checkpath_locked = false; relock: doingdirectory = newparent = false; error = vn_lock(fdvp, LK_EXCLUSIVE); if (error != 0) goto releout; if (vn_lock(tdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { VOP_UNLOCK(fdvp); error = vn_lock(tdvp, LK_EXCLUSIVE); if (error != 0) goto releout; VOP_UNLOCK(tdvp); goto relock; } error = msdosfs_lookup_ino(fdvp, NULL, fcnp, &scn, &blkoff); if (error != 0) { VOP_UNLOCK(fdvp); VOP_UNLOCK(tdvp); goto releout; } error = deget(pmp, scn, blkoff, LK_EXCLUSIVE | LK_NOWAIT, &nip); if (error != 0) { VOP_UNLOCK(fdvp); VOP_UNLOCK(tdvp); if (error != EBUSY) goto releout; error = deget(pmp, scn, blkoff, LK_EXCLUSIVE, &nip); if (error != 0) goto releout; vp = fvp; fvp = DETOV(nip); VOP_UNLOCK(fvp); vrele(vp); goto relock; } vrele(fvp); fvp = DETOV(nip); error = msdosfs_lookup_ino(tdvp, NULL, tcnp, &scn, &blkoff); if (error != 0 && error != EJUSTRETURN) { VOP_UNLOCK(fdvp); VOP_UNLOCK(tdvp); VOP_UNLOCK(fvp); goto releout; } if (error == EJUSTRETURN && tvp != NULL) { vrele(tvp); tvp = NULL; } if (error == 0) { nip = NULL; error = deget(pmp, scn, blkoff, LK_EXCLUSIVE | LK_NOWAIT, &nip); if (tvp != NULL) { vrele(tvp); tvp = NULL; } if (error != 0) { VOP_UNLOCK(fdvp); VOP_UNLOCK(tdvp); VOP_UNLOCK(fvp); if (error != EBUSY) goto releout; error = deget(pmp, scn, blkoff, LK_EXCLUSIVE, &nip); if (error != 0) goto releout; vput(DETOV(nip)); goto relock; } tvp = DETOV(nip); } fdip = VTODE(fdvp); fip = VTODE(fvp); tdip = VTODE(tdvp); tip = tvp != NULL ? VTODE(tvp) : NULL; /* * Remember direntry place to use for destination */ to_diroffset = tdip->de_fndoffset; /* * Be sure we are not renaming ".", "..", or an alias of ".". This * leads to a crippled directory tree. It's pretty tough to do a * "ls" or "pwd" with the "." directory entry missing, and "cd .." * doesn't work if the ".." entry is missing. */ if ((fip->de_Attributes & ATTR_DIRECTORY) != 0) { /* * Avoid ".", "..", and aliases of "." for obvious reasons. */ if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') || fdip == fip || (fcnp->cn_flags & ISDOTDOT) != 0 || (tcnp->cn_flags & ISDOTDOT) != 0) { error = EINVAL; goto unlock; } doingdirectory = true; } /* * If ".." must be changed (ie the directory gets a new * parent) then the source directory must not be in the * directory hierarchy above the target, as this would * orphan everything below the source directory. Also * the user must have write permission in the source so * as to be able to change "..". We must repeat the call * to namei, as the parent directory is unlocked by the * call to doscheckpath(). */ error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, curthread); if (fdip->de_StartCluster != tdip->de_StartCluster) newparent = true; if (doingdirectory && newparent) { if (error != 0) /* write access check above */ goto unlock; lockmgr(&pmp->pm_checkpath_lock, LK_EXCLUSIVE, NULL); checkpath_locked = true; error = doscheckpath(fip, tdip, &wait_scn); if (wait_scn != 0) { lockmgr(&pmp->pm_checkpath_lock, LK_RELEASE, NULL); checkpath_locked = false; VOP_UNLOCK(fdvp); VOP_UNLOCK(tdvp); VOP_UNLOCK(fvp); if (tvp != NULL && tvp != tdvp) VOP_UNLOCK(tvp); error = deget(pmp, wait_scn, 0, LK_EXCLUSIVE, &nip); if (error == 0) { vput(DETOV(nip)); goto relock; } } if (error != 0) goto unlock; } if (tip != NULL) { /* * Target must be empty if a directory and have no links * to it. Also, ensure source and target are compatible * (both directories, or both not directories). */ if ((tip->de_Attributes & ATTR_DIRECTORY) != 0) { if (!dosdirempty(tip)) { error = ENOTEMPTY; goto unlock; } if (!doingdirectory) { error = ENOTDIR; goto unlock; } cache_purge(tdvp); } else if (doingdirectory) { error = EISDIR; goto unlock; } error = msdosfs_lookup_ino(tdvp, NULL, tcnp, &scn, &blkoff); MPASS(error == 0); error = removede(tdip, tip); if (error != 0) goto unlock; vput(tvp); tvp = NULL; tip = NULL; } /* * Convert the filename in tcnp into a dos filename. We copy this * into the denode and directory entry for the destination * file/directory. */ error = uniqdosname(tdip, tcnp, toname); if (error != 0) goto unlock; /* * First write a new entry in the destination * directory and mark the entry in the source directory * as deleted. Then move the denode to the correct hash * chain for its new location in the filesystem. And, if * we moved a directory, then update its .. entry to point * to the new parent directory. */ memcpy(oldname, fip->de_Name, 11); memcpy(fip->de_Name, toname, 11); /* update denode */ error = msdosfs_lookup_ino(tdvp, NULL, tcnp, &scn, &blkoff); MPASS(error == EJUSTRETURN); error = createde(fip, tdip, NULL, tcnp); if (error != 0) { memcpy(fip->de_Name, oldname, 11); goto unlock; } /* * If fip is for a directory, then its name should always * be "." since it is for the directory entry in the * directory itself (msdosfs_lookup() always translates * to the "." entry so as to get a unique denode, except * for the root directory there are different * complications). However, we just corrupted its name * to pass the correct name to createde(). Undo this. */ if ((fip->de_Attributes & ATTR_DIRECTORY) != 0) memcpy(fip->de_Name, oldname, 11); fip->de_refcnt++; error = msdosfs_lookup_ino(fdvp, NULL, fcnp, &scn, &blkoff); MPASS(error == 0); error = removede(fdip, fip); if (error != 0) { /* XXX should downgrade to ro here, fs is corrupt */ goto unlock; } if (!doingdirectory) { error = pcbmap(tdip, de_cluster(pmp, to_diroffset), 0, &fip->de_dirclust, 0); if (error != 0) { /* * XXX should downgrade to ro here, * fs is corrupt */ goto unlock; } if (fip->de_dirclust == MSDOSFSROOT) fip->de_diroffset = to_diroffset; else fip->de_diroffset = to_diroffset & pmp->pm_crbomask; } reinsert(fip); /* * If we moved a directory to a new parent directory, then we must * fixup the ".." entry in the moved directory. */ if (doingdirectory && newparent) { cn = fip->de_StartCluster; if (cn == MSDOSFSROOT) { /* this should never happen */ panic("msdosfs_rename(): updating .. in root directory?"); } else bn = cntobn(pmp, cn); error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, NOCRED, &bp); if (error != 0) { /* XXX should downgrade to ro here, fs is corrupt */ goto unlock; } dotdotp = (struct direntry *)bp->b_data + 1; pcl = tdip->de_StartCluster; if (FAT32(pmp) && pcl == pmp->pm_rootdirblk) pcl = MSDOSFSROOT; putushort(dotdotp->deStartCluster, pcl); if (FAT32(pmp)) putushort(dotdotp->deHighClust, pcl >> 16); if (DOINGASYNC(fvp)) bdwrite(bp); else if ((error = bwrite(bp)) != 0) { /* XXX should downgrade to ro here, fs is corrupt */ goto unlock; } } /* * The msdosfs lookup is case insensitive. Several aliases may * be inserted for a single directory entry. As a consequnce, * name cache purge done by lookup for fvp when DELETE op for * namei is specified, might be not enough to expunge all * namecache entries that were installed for this direntry. */ cache_purge(fvp); unlock: if (checkpath_locked) lockmgr(&pmp->pm_checkpath_lock, LK_RELEASE, NULL); vput(fdvp); vput(fvp); if (tvp != NULL) { if (tvp != tdvp) vput(tvp); else vrele(tvp); } vput(tdvp); return (error); releout: MPASS(!checkpath_locked); vrele(tdvp); if (tvp != NULL) vrele(tvp); vrele(fdvp); vrele(fvp); return (error); abortit: if (tdvp == tvp) vrele(tdvp); else vput(tdvp); if (tvp != NULL) vput(tvp); vrele(fdvp); vrele(fvp); return (error); } static struct { struct direntry dot; struct direntry dotdot; } dosdirtemplate = { { ". ", /* the . entry */ ATTR_DIRECTORY, /* file attribute */ 0, /* reserved */ 0, { 0, 0 }, { 0, 0 }, /* create time & date */ { 0, 0 }, /* access date */ { 0, 0 }, /* high bits of start cluster */ { 210, 4 }, { 210, 4 }, /* modify time & date */ { 0, 0 }, /* startcluster */ { 0, 0, 0, 0 } /* filesize */ }, { ".. ", /* the .. entry */ ATTR_DIRECTORY, /* file attribute */ 0, /* reserved */ 0, { 0, 0 }, { 0, 0 }, /* create time & date */ { 0, 0 }, /* access date */ { 0, 0 }, /* high bits of start cluster */ { 210, 4 }, { 210, 4 }, /* modify time & date */ { 0, 0 }, /* startcluster */ { 0, 0, 0, 0 } /* filesize */ } }; static int msdosfs_mkdir(struct vop_mkdir_args *ap) { struct componentname *cnp = ap->a_cnp; struct denode *dep; struct denode *pdep = VTODE(ap->a_dvp); struct direntry *denp; struct msdosfsmount *pmp = pdep->de_pmp; struct buf *bp; u_long newcluster, pcl; int bn; int error; struct denode ndirent; struct timespec ts; /* * If this is the root directory and there is no space left we * can't do anything. This is because the root directory can not * change size. */ if (pdep->de_StartCluster == MSDOSFSROOT && pdep->de_fndoffset >= pdep->de_FileSize) { error = ENOSPC; goto bad2; } /* * Allocate a cluster to hold the about to be created directory. */ error = clusteralloc(pmp, 0, 1, CLUST_EOFE, &newcluster, NULL); if (error) goto bad2; memset(&ndirent, 0, sizeof(ndirent)); ndirent.de_pmp = pmp; ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE; vfs_timestamp(&ts); DETIMES(&ndirent, &ts, &ts, &ts); /* * Now fill the cluster with the "." and ".." entries. And write * the cluster to disk. This way it is there for the parent * directory to be pointing at if there were a crash. */ bn = cntobn(pmp, newcluster); /* always succeeds */ bp = getblk(pmp->pm_devvp, bn, pmp->pm_bpcluster, 0, 0, 0); memset(bp->b_data, 0, pmp->pm_bpcluster); memcpy(bp->b_data, &dosdirtemplate, sizeof dosdirtemplate); denp = (struct direntry *)bp->b_data; putushort(denp[0].deStartCluster, newcluster); putushort(denp[0].deCDate, ndirent.de_CDate); putushort(denp[0].deCTime, ndirent.de_CTime); denp[0].deCHundredth = ndirent.de_CHun; putushort(denp[0].deADate, ndirent.de_ADate); putushort(denp[0].deMDate, ndirent.de_MDate); putushort(denp[0].deMTime, ndirent.de_MTime); pcl = pdep->de_StartCluster; /* * Although the root directory has a non-magic starting cluster * number for FAT32, chkdsk and fsck_msdosfs still require * references to it in dotdot entries to be magic. */ if (FAT32(pmp) && pcl == pmp->pm_rootdirblk) pcl = MSDOSFSROOT; putushort(denp[1].deStartCluster, pcl); putushort(denp[1].deCDate, ndirent.de_CDate); putushort(denp[1].deCTime, ndirent.de_CTime); denp[1].deCHundredth = ndirent.de_CHun; putushort(denp[1].deADate, ndirent.de_ADate); putushort(denp[1].deMDate, ndirent.de_MDate); putushort(denp[1].deMTime, ndirent.de_MTime); if (FAT32(pmp)) { putushort(denp[0].deHighClust, newcluster >> 16); putushort(denp[1].deHighClust, pcl >> 16); } if (DOINGASYNC(ap->a_dvp)) bdwrite(bp); else if ((error = bwrite(bp)) != 0) goto bad; /* * Now build up a directory entry pointing to the newly allocated * cluster. This will be written to an empty slot in the parent * directory. */ error = uniqdosname(pdep, cnp, ndirent.de_Name); if (error) goto bad; ndirent.de_Attributes = ATTR_DIRECTORY; ndirent.de_LowerCase = 0; ndirent.de_StartCluster = newcluster; ndirent.de_FileSize = 0; error = createde(&ndirent, pdep, &dep, cnp); if (error) goto bad; *ap->a_vpp = DETOV(dep); return (0); bad: clusterfree(pmp, newcluster); bad2: return (error); } static int msdosfs_rmdir(struct vop_rmdir_args *ap) { struct vnode *vp = ap->a_vp; struct vnode *dvp = ap->a_dvp; struct componentname *cnp = ap->a_cnp; struct denode *ip, *dp; int error; ip = VTODE(vp); dp = VTODE(dvp); /* * Verify the directory is empty (and valid). * (Rmdir ".." won't be valid since * ".." will contain a reference to * the current directory and thus be * non-empty.) */ error = 0; if (!dosdirempty(ip)) { error = ENOTEMPTY; goto out; } /* * Delete the entry from the directory. For dos filesystems this * gets rid of the directory entry on disk, the in memory copy * still exists but the de_refcnt is <= 0. This prevents it from * being found by deget(). When the vput() on dep is done we give * up access and eventually msdosfs_reclaim() will be called which * will remove it from the denode cache. */ error = removede(dp, ip); if (error) goto out; /* * This is where we decrement the link count in the parent * directory. Since dos filesystems don't do this we just purge * the name cache. */ cache_purge(dvp); /* * Truncate the directory that is being deleted. */ error = detrunc(ip, (u_long)0, IO_SYNC, cnp->cn_cred); cache_purge(vp); out: return (error); } /* * DOS filesystems don't know what symlinks are. */ static int msdosfs_symlink(struct vop_symlink_args *ap) { return (EOPNOTSUPP); } static int msdosfs_readdir(struct vop_readdir_args *ap) { struct mbnambuf nb; int error = 0; int diff; long n; int blsize; long on; u_long cn; u_long dirsperblk; long bias = 0; daddr_t bn, lbn; struct buf *bp; struct denode *dep = VTODE(ap->a_vp); struct msdosfsmount *pmp = dep->de_pmp; struct direntry *dentp; struct dirent dirbuf; struct uio *uio = ap->a_uio; uint64_t *cookies = NULL; int ncookies = 0; off_t offset, off; int chksum = -1; #ifdef MSDOSFS_DEBUG printf("msdosfs_readdir(): vp %p, uio %p, cred %p, eofflagp %p\n", ap->a_vp, uio, ap->a_cred, ap->a_eofflag); #endif /* * msdosfs_readdir() won't operate properly on regular files since * it does i/o only with the filesystem vnode, and hence can * retrieve the wrong block from the buffer cache for a plain file. * So, fail attempts to readdir() on a plain file. */ if ((dep->de_Attributes & ATTR_DIRECTORY) == 0) return (ENOTDIR); /* * To be safe, initialize dirbuf */ memset(dirbuf.d_name, 0, sizeof(dirbuf.d_name)); /* * If the user buffer is smaller than the size of one dos directory * entry or the file offset is not a multiple of the size of a * directory entry, then we fail the read. */ off = offset = uio->uio_offset; if (uio->uio_resid < sizeof(struct direntry) || (offset & (sizeof(struct direntry) - 1))) return (EINVAL); if (ap->a_ncookies) { ncookies = uio->uio_resid / 16; cookies = malloc(ncookies * sizeof(*cookies), M_TEMP, M_WAITOK); *ap->a_cookies = cookies; *ap->a_ncookies = ncookies; } dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry); /* * If they are reading from the root directory then, we simulate * the . and .. entries since these don't exist in the root * directory. We also set the offset bias to make up for having to * simulate these entries. By this I mean that at file offset 64 we * read the first entry in the root directory that lives on disk. */ if (dep->de_StartCluster == MSDOSFSROOT || (FAT32(pmp) && dep->de_StartCluster == pmp->pm_rootdirblk)) { #if 0 printf("msdosfs_readdir(): going after . or .. in root dir, offset %d\n", offset); #endif bias = 2 * sizeof(struct direntry); if (offset < bias) { for (n = (int)offset / sizeof(struct direntry); n < 2; n++) { dirbuf.d_fileno = FAT32(pmp) ? (uint64_t)cntobn(pmp, pmp->pm_rootdirblk) * dirsperblk : 1; dirbuf.d_type = DT_DIR; switch (n) { case 0: dirbuf.d_namlen = 1; dirbuf.d_name[0] = '.'; break; case 1: dirbuf.d_namlen = 2; dirbuf.d_name[0] = '.'; dirbuf.d_name[1] = '.'; break; } dirbuf.d_reclen = GENERIC_DIRSIZ(&dirbuf); /* NOTE: d_off is the offset of the *next* entry. */ dirbuf.d_off = offset + sizeof(struct direntry); dirent_terminate(&dirbuf); if (uio->uio_resid < dirbuf.d_reclen) goto out; error = uiomove(&dirbuf, dirbuf.d_reclen, uio); if (error) goto out; offset += sizeof(struct direntry); off = offset; if (cookies) { *cookies++ = offset; if (--ncookies <= 0) goto out; } } } } mbnambuf_init(&nb); off = offset; while (uio->uio_resid > 0) { lbn = de_cluster(pmp, offset - bias); on = (offset - bias) & pmp->pm_crbomask; n = min(pmp->pm_bpcluster - on, uio->uio_resid); diff = dep->de_FileSize - (offset - bias); if (diff <= 0) break; n = min(n, diff); error = pcbmap(dep, lbn, &bn, &cn, &blsize); if (error) break; error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp); if (error) { return (error); } n = min(n, blsize - bp->b_resid); if (n == 0) { brelse(bp); return (EIO); } /* * Convert from dos directory entries to fs-independent * directory entries. */ for (dentp = (struct direntry *)(bp->b_data + on); (char *)dentp < bp->b_data + on + n; dentp++, offset += sizeof(struct direntry)) { #if 0 printf("rd: dentp %08x prev %08x crnt %08x deName %02x attr %02x\n", dentp, prev, crnt, dentp->deName[0], dentp->deAttributes); #endif /* * If this is an unused entry, we can stop. */ if (dentp->deName[0] == SLOT_EMPTY) { brelse(bp); goto out; } /* * Skip deleted entries. */ if (dentp->deName[0] == SLOT_DELETED) { chksum = -1; mbnambuf_init(&nb); continue; } /* * Handle Win95 long directory entries */ if (dentp->deAttributes == ATTR_WIN95) { if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME) continue; chksum = win2unixfn(&nb, (struct winentry *)dentp, chksum, pmp); continue; } /* * Skip volume labels */ if (dentp->deAttributes & ATTR_VOLUME) { chksum = -1; mbnambuf_init(&nb); continue; } /* * This computation of d_fileno must match * the computation of va_fileid in * msdosfs_getattr. */ if (dentp->deAttributes & ATTR_DIRECTORY) { cn = getushort(dentp->deStartCluster); if (FAT32(pmp)) { cn |= getushort(dentp->deHighClust) << 16; if (cn == MSDOSFSROOT) cn = pmp->pm_rootdirblk; } if (cn == MSDOSFSROOT && !FAT32(pmp)) dirbuf.d_fileno = 1; else dirbuf.d_fileno = cntobn(pmp, cn) * dirsperblk; dirbuf.d_type = DT_DIR; } else { dirbuf.d_fileno = (uoff_t)offset / sizeof(struct direntry); dirbuf.d_type = DT_REG; } if (chksum != winChksum(dentp->deName)) { dirbuf.d_namlen = dos2unixfn(dentp->deName, (u_char *)dirbuf.d_name, dentp->deLowerCase | ((pmp->pm_flags & MSDOSFSMNT_SHORTNAME) ? (LCASE_BASE | LCASE_EXT) : 0), pmp); mbnambuf_init(&nb); } else mbnambuf_flush(&nb, &dirbuf); chksum = -1; dirbuf.d_reclen = GENERIC_DIRSIZ(&dirbuf); /* NOTE: d_off is the offset of the *next* entry. */ dirbuf.d_off = offset + sizeof(struct direntry); dirent_terminate(&dirbuf); if (uio->uio_resid < dirbuf.d_reclen) { brelse(bp); goto out; } error = uiomove(&dirbuf, dirbuf.d_reclen, uio); if (error) { brelse(bp); goto out; } if (cookies) { *cookies++ = offset + sizeof(struct direntry); if (--ncookies <= 0) { brelse(bp); goto out; } } off = offset + sizeof(struct direntry); } brelse(bp); } out: /* Subtract unused cookies */ if (ap->a_ncookies) *ap->a_ncookies -= ncookies; uio->uio_offset = off; /* * Set the eofflag (NFS uses it) */ if (ap->a_eofflag) { if (dep->de_FileSize - (offset - bias) <= 0) *ap->a_eofflag = 1; else *ap->a_eofflag = 0; } return (error); } /*- * a_vp - pointer to the file's vnode * a_bn - logical block number within the file (cluster number for us) * a_bop - where to return the bufobj of the special file containing the fs * a_bnp - where to return the "physical" block number corresponding to a_bn * (relative to the special file; units are blocks of size DEV_BSIZE) * a_runp - where to return the "run past" a_bn. This is the count of logical * blocks whose physical blocks (together with a_bn's physical block) * are contiguous. * a_runb - where to return the "run before" a_bn. */ static int msdosfs_bmap(struct vop_bmap_args *ap) { struct fatcache savefc; struct denode *dep; struct mount *mp; struct msdosfsmount *pmp; struct vnode *vp; daddr_t runbn; u_long cn; int bnpercn, error, maxio, maxrun, run; vp = ap->a_vp; dep = VTODE(vp); pmp = dep->de_pmp; if (ap->a_bop != NULL) *ap->a_bop = &pmp->pm_devvp->v_bufobj; if (ap->a_bnp == NULL) return (0); if (ap->a_runp != NULL) *ap->a_runp = 0; if (ap->a_runb != NULL) *ap->a_runb = 0; cn = ap->a_bn; if (cn != ap->a_bn) return (EFBIG); error = pcbmap(dep, cn, ap->a_bnp, NULL, NULL); if (error != 0 || (ap->a_runp == NULL && ap->a_runb == NULL)) return (error); /* * Prepare to back out updates of the fatchain cache after the one * for the first block done by pcbmap() above. Without the backout, * then whenever the caller doesn't do i/o to all of the blocks that * we find, the single useful cache entry would be too far in advance * of the actual i/o to work for the next sequential i/o. Then the * FAT would be searched from the beginning. With the backout, the * FAT is searched starting at most a few blocks early. This wastes * much less time. Time is also wasted finding more blocks than the * caller will do i/o to. This is necessary because the runlength * parameters are output-only. */ savefc = dep->de_fc[FC_LASTMAP]; mp = vp->v_mount; maxio = mp->mnt_iosize_max / mp->mnt_stat.f_iosize; bnpercn = de_cn2bn(pmp, 1); if (ap->a_runp != NULL) { maxrun = ulmin(maxio - 1, pmp->pm_maxcluster - cn); for (run = 1; run <= maxrun; run++) { if (pcbmap(dep, cn + run, &runbn, NULL, NULL) != 0 || runbn != *ap->a_bnp + run * bnpercn) break; } *ap->a_runp = run - 1; } if (ap->a_runb != NULL) { maxrun = ulmin(maxio - 1, cn); for (run = 1; run < maxrun; run++) { if (pcbmap(dep, cn - run, &runbn, NULL, NULL) != 0 || runbn != *ap->a_bnp - run * bnpercn) break; } *ap->a_runb = run - 1; } dep->de_fc[FC_LASTMAP] = savefc; return (0); } SYSCTL_NODE(_vfs, OID_AUTO, msdosfs, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "msdos filesystem"); static int use_buf_pager = 1; SYSCTL_INT(_vfs_msdosfs, OID_AUTO, use_buf_pager, CTLFLAG_RWTUN, &use_buf_pager, 0, "Use buffer pager instead of bmap"); static daddr_t msdosfs_gbp_getblkno(struct vnode *vp, vm_ooffset_t off) { return (de_cluster(VTODE(vp)->de_pmp, off)); } static int msdosfs_gbp_getblksz(struct vnode *vp, daddr_t lbn, long *sz) { *sz = VTODE(vp)->de_pmp->pm_bpcluster; return (0); } static int msdosfs_getpages(struct vop_getpages_args *ap) { if (use_buf_pager) return (vfs_bio_getpages(ap->a_vp, ap->a_m, ap->a_count, ap->a_rbehind, ap->a_rahead, msdosfs_gbp_getblkno, msdosfs_gbp_getblksz)); return (vnode_pager_generic_getpages(ap->a_vp, ap->a_m, ap->a_count, ap->a_rbehind, ap->a_rahead, NULL, NULL)); } static int msdosfs_strategy(struct vop_strategy_args *ap) { struct buf *bp = ap->a_bp; struct denode *dep = VTODE(ap->a_vp); struct bufobj *bo; int error = 0; daddr_t blkno; /* * If we don't already know the filesystem relative block number * then get it using pcbmap(). If pcbmap() returns the block * number as -1 then we've got a hole in the file. DOS filesystems * don't allow files with holes, so we shouldn't ever see this. */ if (bp->b_blkno == bp->b_lblkno) { error = pcbmap(dep, bp->b_lblkno, &blkno, 0, 0); bp->b_blkno = blkno; if (error) { bp->b_error = error; bp->b_ioflags |= BIO_ERROR; bufdone(bp); return (0); } if ((long)bp->b_blkno == -1) vfs_bio_clrbuf(bp); } if (bp->b_blkno == -1) { bufdone(bp); return (0); } /* * Read/write the block from/to the disk that contains the desired * file block. */ bp->b_iooffset = dbtob(bp->b_blkno); bo = dep->de_pmp->pm_bo; BO_STRATEGY(bo, bp); return (0); } static int msdosfs_print(struct vop_print_args *ap) { struct denode *dep = VTODE(ap->a_vp); printf("\tstartcluster %lu, dircluster %lu, diroffset %lu, ", dep->de_StartCluster, dep->de_dirclust, dep->de_diroffset); printf("on dev %s\n", devtoname(dep->de_pmp->pm_dev)); return (0); } static int msdosfs_pathconf(struct vop_pathconf_args *ap) { struct msdosfsmount *pmp = VTODE(ap->a_vp)->de_pmp; switch (ap->a_name) { case _PC_FILESIZEBITS: *ap->a_retval = 32; return (0); case _PC_LINK_MAX: *ap->a_retval = 1; return (0); case _PC_NAME_MAX: *ap->a_retval = pmp->pm_flags & MSDOSFSMNT_LONGNAME ? WIN_MAXLEN : 12; return (0); case _PC_CHOWN_RESTRICTED: *ap->a_retval = 1; return (0); case _PC_NO_TRUNC: *ap->a_retval = 0; return (0); default: return (vop_stdpathconf(ap)); } /* NOTREACHED */ } static int msdosfs_vptofh(struct vop_vptofh_args *ap) { struct denode *dep; struct defid *defhp; dep = VTODE(ap->a_vp); defhp = (struct defid *)ap->a_fhp; defhp->defid_len = sizeof(struct defid); defhp->defid_dirclust = dep->de_dirclust; defhp->defid_dirofs = dep->de_diroffset; /* defhp->defid_gen = dep->de_gen; */ return (0); } /* Global vfs data structures for msdosfs */ struct vop_vector msdosfs_vnodeops = { .vop_default = &default_vnodeops, .vop_access = msdosfs_access, .vop_bmap = msdosfs_bmap, .vop_getpages = msdosfs_getpages, .vop_cachedlookup = msdosfs_lookup, .vop_open = msdosfs_open, .vop_close = msdosfs_close, .vop_create = msdosfs_create, .vop_fsync = msdosfs_fsync, .vop_fdatasync = vop_stdfdatasync_buf, .vop_getattr = msdosfs_getattr, .vop_inactive = msdosfs_inactive, .vop_link = msdosfs_link, .vop_lookup = vfs_cache_lookup, .vop_mkdir = msdosfs_mkdir, .vop_mknod = msdosfs_mknod, .vop_pathconf = msdosfs_pathconf, .vop_print = msdosfs_print, .vop_read = msdosfs_read, .vop_readdir = msdosfs_readdir, .vop_reclaim = msdosfs_reclaim, .vop_remove = msdosfs_remove, .vop_rename = msdosfs_rename, .vop_rmdir = msdosfs_rmdir, .vop_setattr = msdosfs_setattr, .vop_strategy = msdosfs_strategy, .vop_symlink = msdosfs_symlink, .vop_write = msdosfs_write, .vop_vptofh = msdosfs_vptofh, }; VFS_VOP_VECTOR_REGISTER(msdosfs_vnodeops);